The scientific question is how do we correctly interpret why EE pads seem
to outperform FF pads in this police cruiser study done in 2000?
https://www.justnet.org/pdf/EvaluationBrakePads2000.pdf
https://www.justnet.org/pdf/Copy-of-...port-Draft.pdf

In another thread today, the topic was discussed on how to intelligently
select friction materials for replacement brake pads and shoes.
https://s18.postimg.org/wqilqasdl/to...n_material.jpg

That discussion hinges on a scientifically valid interpretation and
understanding of the utility of the "friction codes" printed on every brake
pad and shoe in the USA:
AMECA Compliance List of Automotive Safety Devices:
Friction Material Edge Codes(TM), May 2011
http://safebraking.com/wp-content/uploads/2013/02/AMECA-List-of-VESC-V-3-Brake-Friction-Material-Edge-Codes-May-20112.pdf

A general summary of which is listed below:
http://faculty.ccbcmd.edu/~smacadof/DOTPadCodes.htm
https://netrider.net.au/threads/unde...ratings.88551/
http://www.hotrod.com/articles/hrdp-...ad-technology/
etc.

The scientific question is how do we correctly interpret why EE pads seem
to outperform FF pads in this police cruiser study done in 2000?
https://www.justnet.org/pdf/EvaluationBrakePads2000.pdf

On Thu, 11 Jan 2018 02:47:38 -0000 (UTC),
Mad Roger wrote:

The scientific question is how do we correctly interpret why EE pads seem
to outperform FF pads in this police cruiser study done in 2000?
https://www.justnet.org/pdf/EvaluationBrakePads2000.pdf

Here is the original response to that thread where it was said that SAE
J866a Chase Test EE pads outperformed FF pads.
https://groups.google.com/d/msg/rec.autos.tech/_SSZmTXS5kk/87MU4e1JAAAJ

I can't run my own tests like the police did he
https://www.justnet.org/pdf/EvaluationBrakePads2000.pdf

And those tests showed the EE pads CONSISTENTLY outperformed the
FF brakes pretty well across the board - with the FF brakes
SEVERELY underperforming in most cases.

The Dana Ceramic family was the only FF to outperform OEM, while
HawkHead outperformed on both Chevy and Ford - and Raybestos and
Carquest alsooutperformed on Ford in the panic stop test.

Across the board, EE brakes, on the whole, outperformed the FF
and even the EE/GG combination - so what does your friction
rating tell you????????????

What it tells ME is if I buy Raybestos, NAPA, CVarquest, or Dana
(all major OEM suppliers) brakes, I will equal or excede OEM
performance - doesn't make a bit of difference to me WHAT rating
they have.

If I want slightly superior hot panic braking, at the expense
of poorer cold and medium temperature braking I should buy
ceramics - and this is STRICTLY for braking performance.

Now, from REAL WORLD experience, both myFord Aerostrs went
through rotors like crazy - untill I put on NAPA's Carbon
Metallics a set of pads destroyed a set of rotors at about
half of pad life - and I mean TOTALLY DESTROYED, here in
Southern Ontario. That came out at just over a year.

When I went to NAPA Carbon Metallics, the same rotors lasted
for TWO FULL SETS of pads - and over 5 years - and I was able
to actually lock the front wheels on dry pavement (rear ABS only)
- which NONE of the other brakes were capable of doing.

Never looked at the friction rating - never needed to,
because friction rating doesn't tell the whole story
(as your reference so elegantly proved)

You can have 5 different FF pads - and one will be noisy as hell, one
will eat rotors for lunch, onde will corrode as soon as it SMELLS
salt, and another will turn to gravel the first time you get it hot -
ALL FF rated (or ef, or ee. or FE )

The fact it met the test requirements ONCE in the lab means NOTHING
about quality

On 1/10/18 8:47 PM, Mad Roger wrote:
The scientific question is how

He's back with a new name.
Hopefully this means the end of the Apple thread.



--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

On 11/01/2018 1:47 PM, Mad Roger wrote:
The scientific question is how do we correctly interpret why EE pads seem

The scientific results are back! You are certifiably insane!

to outperform FF pads in this police cruiser study done in 2000?
https://www.justnet.org/pdf/EvaluationBrakePads2000.pdf
https://www.justnet.org/pdf/Copy-of-...port-Draft.pdf

In another thread today, the topic was discussed on how to intelligently
select friction materials for replacement brake pads and shoes.
https://s18.postimg.org/wqilqasdl/to...n_material.jpg

That discussion hinges on a scientifically valid interpretation and
understanding of the utility of the "friction codes" printed on every brake
pad and shoe in the USA:
AMECA Compliance List of Automotive Safety Devices:
Friction Material Edge Codes(TM), May 2011
http://safebraking.com/wp-content/uploads/2013/02/AMECA-List-of-VESC-V-3-Brake-Friction-Material-Edge-Codes-May-20112.pdf

A general summary of which is listed below:
http://faculty.ccbcmd.edu/~smacadof/DOTPadCodes.htm
https://netrider.net.au/threads/unde...ratings.88551/
http://www.hotrod.com/articles/hrdp-...ad-technology/
etc.

The scientific question is how do we correctly interpret why EE pads seem
to outperform FF pads in this police cruiser study done in 2000?
https://www.justnet.org/pdf/EvaluationBrakePads2000.pdf



--

Xeno

On 11/01/2018 2:09 PM, Fox's Mercantile wrote:
On 1/10/18 8:47 PM, Mad Roger wrote:
The scientific question is how

He's back with a new name.

In spades!

Hopefully this means the end of the Apple thread.



But the start of a new, and useless, thread.

--

Xeno

On Thu, 11 Jan 2018 02:47:38 -0000 (UTC), Mad Roger
wrote:

The scientific question is how do we correctly interpret why EE pads seem
to outperform FF pads in this police cruiser study done in 2000?
https://www.justnet.org/pdf/EvaluationBrakePads2000.pdf
https://www.justnet.org/pdf/Copy-of-...port-Draft.pdf

In another thread today, the topic was discussed on how to intelligently
select friction materials for replacement brake pads and shoes.
https://s18.postimg.org/wqilqasdl/to...n_material.jpg

That discussion hinges on a scientifically valid interpretation and
understanding of the utility of the "friction codes" printed on every brake
pad and shoe in the USA:
AMECA Compliance List of Automotive Safety Devices:
Friction Material Edge Codes(TM), May 2011
http://safebraking.com/wp-content/uploads/2013/02/AMECA-List-of-VESC-V-3-Brake-Friction-Material-Edge-Codes-May-20112.pdf

A general summary of which is listed below:
http://faculty.ccbcmd.edu/~smacadof/DOTPadCodes.htm
https://netrider.net.au/threads/unde...ratings.88551/
http://www.hotrod.com/articles/hrdp-...ad-technology/
etc.

The scientific question is how do we correctly interpret why EE pads seem
to outperform FF pads in this police cruiser study done in 2000?
https://www.justnet.org/pdf/EvaluationBrakePads2000.pdf


The engineer's enigma.

And that's with "genuine" parts (we will "ass u me")

Now google "counterfeit brake parts" - or just "counterfeit auto
parts" - and you will see how big a problem parts counterfeiting is
world wide, and why those ratings stamped onthe brakers do not
NECESSARILLY mean ANYTHING.

That's why I say buying known brand parts from a trusted supplier is
the FIRST step in getting good parts.

Assuming coefficient of friction IS the main quality you want in
brakes - which for me it most definitely is NOT.

I want quiet brakes that respond smoothly both hot and cold, last for
a good length of time, and do not destroy my rotors/drums.
On disc brakes I want pads that don't dust excessively, and the dust
does not attack the finish on my alloy rims or wheel covers.
I want brakes that do not fade excessively, and that willprovide more
than adequate braking in real world conditions.

When I installed oversized tires on my Ranger, brake effectiveness
deteriorated significantly - with the same brake pads and rotors.
I'm no engineer - but it was not hard to determine the problem was a
problem of leverage - the big wheels were exerting more foot-lbs of
torque to the brake - and the answer was bigger rotors - NOT different
brake pads - or even bigger brake pads. Just move the brake pads 10%
farther from the axle, like the larger wheels moved the road contact
area about 10% farther from the axle, and the brake force was
re-ballanced.

On Wed, 10 Jan 2018 23:07:18 -0500,
Clare Snyder wrote:

The engineer's enigma.

This is a difficult question to answer, where *Xeno the troll* clearly
isn't capable of answering it, but neither am I, which is why I asked for
scientific help.

We're talking about EE and FF pads as determined by the SAE J866 Chase Test
http://standards.sae.org/j866_201201/

And, we're talking about EE/FF pads being tested in the *same vehicle*,
where one must note the friction coefficient of E is marginally above that
of steel on steel (i.e., no pad at all).

Hence it is an enigma if the EE lower-friction coefficient friction
materials can outperform FF higher-friction coefficient materials in
real-world tests.

However, it is true that the link above says, very clearly:
"Due to other factors that include brake system design and
operating environment, the friction codes obtained from this
document cannot reliably be used to predict brake system performance."

So the only scientific question here is why would EE outperperform FF?

And that's with "genuine" parts (we will "ass u me")

Now google "counterfeit brake parts" - or just "counterfeit auto
parts" - and you will see how big a problem parts counterfeiting is
world wide, and why those ratings stamped onthe brakers do not
NECESSARILLY mean ANYTHING.

While counterfeit parts "could" be the problem, do you really think that a
state-run test posted and published nationally, would fall prey to them?

I think that fails Occam's Razor for logic (unless you have proof).

That's why I say buying known brand parts from a trusted supplier is
the FIRST step in getting good parts.

But we can assume the police did that - where it's just not reasonably
logical that they would fall prey to a plethora of counterfeit parts,
especially since the parts were *supplied* by the manufacturers, I believe.

(We could fall prey to "ringers" though...)

Assuming coefficient of friction IS the main quality you want in
brakes - which for me it most definitely is NOT.

I have to openly admit that I think the coefficient of friction is one of
the critical factors in brake friction materials, other than fit and
"reasonable" everything else (longevity, noise, dust, etc. in the Bell
Curve).

I want quiet brakes that respond smoothly both hot and cold, last for
a good length of time, and do not destroy my rotors/drums.
On disc brakes I want pads that don't dust excessively, and the dust
does not attack the finish on my alloy rims or wheel covers.

Everyone wants that, so we all agree (except trolls like Fox's Mercantile).

But how do you know that from the numbers printed on the pad?
(Rhetorical question - as I know there's no way to know that.)

I want brakes that do not fade excessively, and that willprovide more
than adequate braking in real world conditions.

Why wouldn't fade be covered in the SAE J866 Chase Test, which tests their
friction coefficient at a variety of temperatures?

When I installed oversized tires on my Ranger, brake effectiveness
deteriorated significantly - with the same brake pads and rotors.
I'm no engineer - but it was not hard to determine the problem was a
problem of leverage - the big wheels were exerting more foot-lbs of
torque to the brake - and the answer was bigger rotors - NOT different
brake pads - or even bigger brake pads. Just move the brake pads 10%
farther from the axle, like the larger wheels moved the road contact
area about 10% farther from the axle, and the brake force was
re-ballanced.

I agree that there are *many* factors in the act of slowing down a vehicle
with brake friction material heating up causing a loss of the energy of
momentum.

However, the cold & hot friction coefficient, logically, must be a primary
factor, where there's a reason if lower coefficient EE pads (which have
just barely better a coefficient of friction than no pads at all) could
outperform FF pads (which have appreciably higher friction coefficients) in
the same vehicle under standard tests.

All I ask is how this can happen (where counterfeits are not logically the
reason).

On Thu, 11 Jan 2018 14:46:34 -0000 (UTC), Mad Roger
wrote:

On Wed, 10 Jan 2018 23:07:18 -0500,
Clare Snyder wrote:

The engineer's enigma.

This is a difficult question to answer, where *Xeno the troll* clearly
isn't capable of answering it, but neither am I, which is why I asked for
scientific help.

We're talking about EE and FF pads as determined by the SAE J866 Chase Test
http://standards.sae.org/j866_201201/

And, we're talking about EE/FF pads being tested in the *same vehicle*,
where one must note the friction coefficient of E is marginally above that
of steel on steel (i.e., no pad at all).

Hence it is an enigma if the EE lower-friction coefficient friction
materials can outperform FF higher-friction coefficient materials in
real-world tests.

However, it is true that the link above says, very clearly:
"Due to other factors that include brake system design and
operating environment, the friction codes obtained from this
document cannot reliably be used to predict brake system performance."

So the only scientific question here is why would EE outperperform FF?

And that's with "genuine" parts (we will "ass u me")

Now google "counterfeit brake parts" - or just "counterfeit auto
parts" - and you will see how big a problem parts counterfeiting is
world wide, and why those ratings stamped onthe brakers do not
NECESSARILLY mean ANYTHING.

While counterfeit parts "could" be the problem, do you really think that a
state-run test posted and published nationally, would fall prey to them?

I'm discounting conterfeit parts as being the problemin these tests -
just going back to your "trust" in "government mandated markings" from
your previous thread.

I think that fails Occam's Razor for logic (unless you have proof).

That's why I say buying known brand parts from a trusted supplier is
the FIRST step in getting good parts.

But we can assume the police did that - where it's just not reasonably
logical that they would fall prey to a plethora of counterfeit parts,
especially since the parts were *supplied* by the manufacturers, I believe.

(We could fall prey to "ringers" though...)

No, I'm just saying - again - that depending on the government
mandated friction rating markings will NOT get you the best brake -
which has been my thesis from the beginning and has been proven by TWO
law enforcement vehicle tests you have provided to support your
position.

I'msorry, but your thesis does NOT stand the test of proof using the
scientific method. You are an engineer. What does that tell you???

If it was just a case of FF pads on a dodge undeperforming the same
pad on a Foprd, you could put it down to bake design - but that is not
the case here., There is NO LOGICAL EXPLANATION other than the FACT
that the markings are NOT a reliable predictor of brake performance -
muchless quality.

Assuming coefficient of friction IS the main quality you want in
brakes - which for me it most definitely is NOT.

I have to openly admit that I think the coefficient of friction is one of
the critical factors in brake friction materials, other than fit and
"reasonable" everything else (longevity, noise, dust, etc. in the Bell
Curve).


I puit more weight on the other qualities,as they are readilly evident
- while the friction grade of the material is not - as proven by the
tests.

I want quiet brakes that respond smoothly both hot and cold, last for
a good length of time, and do not destroy my rotors/drums.
On disc brakes I want pads that don't dust excessively, and the dust
does not attack the finish on my alloy rims or wheel covers.

Everyone wants that, so we all agree (except trolls like Fox's Mercantile).

But how do you know that from the numbers printed on the pad?

You don't.

Now another thing that affects HOT braking is the attachment of the
lining to the shoe/pad. Does the "glue" adequately transmit the heat
or act as an insulator?? Personally,I'm a BIG fan of rivetted linings
and pads, rather than bonded.

They are generally quieter,and in my experience exhibit less fade.
They also generakky speaking have a smoother engagement.
(Rhetorical question - as I know there's no way to know that.)

I want brakes that do not fade excessively, and that willprovide more
than adequate braking in real world conditions.

Why wouldn't fade be covered in the SAE J866 Chase Test, which tests their
friction coefficient at a variety of temperatures?

Because the damned tests are either faulty or improerly performed
(the material does not meet the spec) OR the method of mounting does
not properly mitigate the heat.

When I installed oversized tires on my Ranger, brake effectiveness
deteriorated significantly - with the same brake pads and rotors.
I'm no engineer - but it was not hard to determine the problem was a
problem of leverage - the big wheels were exerting more foot-lbs of
torque to the brake - and the answer was bigger rotors - NOT different
brake pads - or even bigger brake pads. Just move the brake pads 10%
farther from the axle, like the larger wheels moved the road contact
area about 10% farther from the axle, and the brake force was
re-ballanced.

I agree that there are *many* factors in the act of slowing down a vehicle
with brake friction material heating up causing a loss of the energy of
momentum.

However, the cold & hot friction coefficient, logically, must be a primary
factor, where there's a reason if lower coefficient EE pads (which have
just barely better a coefficient of friction than no pads at all) could
outperform FF pads (which have appreciably higher friction coefficients) in
the same vehicle under standard tests.

All I ask is how this can happen (where counterfeits are not logically the
reason).


Failure of the testing/certification process to reflect real world
conditions.

Sorry, but you engineers devise the tests. There is definitely
SOMETHING wrong with either the design of the test, the implementation
of the test, (application) or the theory applied.

Which is why I put very limited weight on the stamped/published
friction ratings.

They have been proven time and again to be pretty close to useless.

Now, if you take a, for instance, BRakebond pad with ee, another of
their pads with ef, and another eith ff - there MIGHT be a displayable
progression between them - all other factors being the same (which
they seldom are). Or you may find an ee or ef pad or shoe STILL
outperforms an ff in the real world.

There is a lot more involved in brake performance - particularly hot
performance, than simple coefficent of friction.

gassing from the friction material, and how it is vented, being one
issue. Simply cross-cutting a pad, or chamfering the edge of the pad -
while marginally reducing the active braking area CAN improve hot stop
performance significantly.

In this case, the test using a one square inch sample of pad material
TOTALLY misses the mark - meaning the test design is faulty from the
start.

I'm no engineer - but I know that much!!

When you combine government beaurocrats and engineers with no "real
world" experience to implement ANY program, the chances of failure to
perform get exponentially higher than tests performed under "real
world" conditions.

And as for not using EE friction materials - SOME of the cruisers
used in thase testa use ef or ff material in the
persuit special" vehicles, while civilian and even taxi (heavy duty)
use may have EE from the factory.

The whole CAFE situation, requiring the lightening of all components,
has resulted in a generation of vehicles that are (or have been)
SEVERELY underbraked - and this deficiency has been hidden by the
universalimplementation of antilock brakes - the small brakes canNOT
provide enough braking force to lock the wheels on dry pavement
because, by and large, they do not have to.

As long as the braking action of the brake assembly matches the
friction betweenthe tires and the road, it is accepted.

If I shut off the antilock function of my brakes, I want them to be
capable of throwing the vehicle into a complete slide - on command -
whether hot or cold.

With the oversized brakes (same pads as stock) with ee friction
material on my ranger- I CAN lock all 4 wheels - on command - with
antilock dissabled. - so why would I insist on FF pads, which, by the
results of the tests YOU provided, may very well underperform the "low
grade" ee pads I have installed?????

On Thu, 11 Jan 2018 11:44:01 -0500,
Clare Snyder wrote:

I'm discounting conterfeit parts as being the problemin these tests -
just going back to your "trust" in "government mandated markings" from
your previous thread.

I agree with you that it's unlikely that the police in Michigan were
testing counterfeit parts, especially as they apparently received the
friction material directly from the manufacturer, according to their
summary paper.

(We could fall prey to "ringers" though...)

No, I'm just saying - again - that depending on the government
mandated friction rating markings will NOT get you the best brake -
which has been my thesis from the beginning and has been proven by TWO
law enforcement vehicle tests you have provided to support your
position.

I'm not disagreeing with your contention that the EE pads, in those police
tests, somehow worked better than the FF pads, even though E is a friction
coefficient only marginally higher than steel on steel.

I'm only asking why.

I'msorry, but your thesis does NOT stand the test of proof using the
scientific method. You are an engineer. What does that tell you???

I'm an electrical engineer; so I believe in friction, but if the lower
friction coefficient pads are working better than the higher friction
coefficient pads, the precise understanding of that is out of my league.

That's why I asked here, where I was hoping the s.e.r intelligentsia might
help us rationalize a reason that stands the test of logical analysis.

If it was just a case of FF pads on a dodge undeperforming the same
pad on a Foprd, you could put it down to brake design - but that is not
the case here., There is NO LOGICAL EXPLANATION other than the FACT
that the markings are NOT a reliable predictor of brake performance -
muchless quality.

I agreed with your assessment, and I even quoted the Michigan police
cruiser test warning saying that the markings don't necessarily conform to
real-world practice.

I'm only asking here WHY an E coefficient pad (which is basically no pad at
all) performed better than an F coefficient pad (which has an appreciably
higher cold & hot friction coefficient)?

I puit more weight on the other qualities,as they are readilly evident
- while the friction grade of the material is not - as proven by the
tests.

I'm going to have to somewhat reluctantly agree with you, unless we get a
good reason, that no pad at all (i.e., just metal on metal) is "just as
good" and "maybe even better" than a high friction coefficient pad.

Pretty much that says "all pads work", does it not?

But how do you know that from the numbers printed on the pad?

You don't.

Again, I'm going to have to somewhat reluctantly agree with you, from a
logical standpoint, that if essentially no pad at all (i.e., an E
coefficient pad which has a coefficient of friction marginally better than
steel on steel) is better or about as good as having a pad, then almost
nothing printed on the side of the pad is going to make any difference.

Now another thing that affects HOT braking is the attachment of the
lining to the shoe/pad. Does the "glue" adequately transmit the heat
or act as an insulator?? Personally,I'm a BIG fan of rivetted linings
and pads, rather than bonded.

It seems there *must* be other *major* factors in braking performance,
other than the friction rating of the pads themselves.

That's a hard logical pill to swallow, for me, which is why I asked here,
hoping the s.e.r folks can enlighten us as to why.

Failure of the testing/certification process to reflect real world
conditions.

Well, the friction coefficient is a "real world" measurement.

It just doesn't seem to matter in braking performance, based on that police
cruiser test I unearthed.

That's too bad, because it means you can't compare pads easily other than
to note the material, type, and manufacturer, which the DOT CODES printed
on each pad and shoe do tell you.

So at least we can tell three pads with three different marketing
strategies (e.g, Axxis, PBR, & Metal Masters) are the exact *same* pad, and
we can tell when a pad is rebranded (I think Centric only does rebranded
pads, for example, but I'd have to check the numbers to be sure).

That indicates there is some utility in the mandated information that is
printed on the side of each pad.

But it's just sad that the friction coefficient means so little to a
friction material!

Sorry, but you engineers devise the tests. There is definitely
SOMETHING wrong with either the design of the test, the implementation
of the test, (application) or the theory applied.

Friction is friction.
It's a mathematical beast.

I don't think the SAE J866 Chase Tests lie about the friction of a 1"
square piece of the friction material.

They just don't predict real-world performance, it seems.
(As noted in the Police Cruiser report.)

Which is why I put very limited weight on the stamped/published
friction ratings.

Again, I must reluctantly agree with you, as hard a pill as it is to
swallow, that friction coefficients are NOT an important factor in the
performance of brake friction materials.

Sigh.

I just want to know WHY?

They have been proven time and again to be pretty close to useless.

Well, as I said, the *numbers* printed on the side of every pad/shoe sold
in the USA are *useful* in that they tell you the manufacturer, the
material, and, the friction rating - so even if we discount the friction
rating, it's nice to know when you can tell that two pads sold and marketed
at two different prices, are the same pad.

Now, if you take a, for instance, BRakebond pad with ee, another of
their pads with ef, and another eith ff - there MIGHT be a displayable
progression between them - all other factors being the same (which
they seldom are). Or you may find an ee or ef pad or shoe STILL
outperforms an ff in the real world.

I'm gonna have to reluctantly agree with you, yet again.
I don't ever dispute fact.

There is a lot more involved in brake performance - particularly hot
performance, than simple coefficent of friction.

It must be the case that friction isn't a *primary* determinant of brake
performance, hard a pill as that is to swallow.

In this case, the test using a one square inch sample of pad material
TOTALLY misses the mark - meaning the test design is faulty from the
start.

You'd think the SAE would know how to design a friction test though...

And as for not using EE friction materials - SOME of the cruisers
used in thase testa use ef or ff material in the
persuit special" vehicles, while civilian and even taxi (heavy duty)
use may have EE from the factory.

I know. I know. You don't have to rub it in.
I apologize for chastening you for using EE pads and shoes.

I still think my Toyota OEM shoes are FF so I'm gonna get FF.
Can you summarize again the short list of brands you'd recommend?
I want to do the work for the owner this weekend.

Thanks.

On Thu, 11 Jan 2018 20:09:25 -0000 (UTC), Mad Roger
wrote:

On Thu, 11 Jan 2018 11:44:01 -0500,
Clare Snyder wrote:

I'm discounting conterfeit parts as being the problemin these tests -
just going back to your "trust" in "government mandated markings" from
your previous thread.

I agree with you that it's unlikely that the police in Michigan were
testing counterfeit parts, especially as they apparently received the
friction material directly from the manufacturer, according to their
summary paper.

(We could fall prey to "ringers" though...)

No, I'm just saying - again - that depending on the government
mandated friction rating markings will NOT get you the best brake -
which has been my thesis from the beginning and has been proven by TWO
law enforcement vehicle tests you have provided to support your
position.

I'm not disagreeing with your contention that the EE pads, in those police
tests, somehow worked better than the FF pads, even though E is a friction
coefficient only marginally higher than steel on steel.

I'm only asking why.

I'msorry, but your thesis does NOT stand the test of proof using the
scientific method. You are an engineer. What does that tell you???

I'm an electrical engineer; so I believe in friction, but if the lower
friction coefficient pads are working better than the higher friction
coefficient pads, the precise understanding of that is out of my league.

That's why I asked here, where I was hoping the s.e.r intelligentsia might
help us rationalize a reason that stands the test of logical analysis.

If it was just a case of FF pads on a dodge undeperforming the same
pad on a Foprd, you could put it down to brake design - but that is not
the case here., There is NO LOGICAL EXPLANATION other than the FACT
that the markings are NOT a reliable predictor of brake performance -
muchless quality.

I agreed with your assessment, and I even quoted the Michigan police
cruiser test warning saying that the markings don't necessarily conform to
real-world practice.

I'm only asking here WHY an E coefficient pad (which is basically no pad at
all) performed better than an F coefficient pad (which has an appreciably
higher cold & hot friction coefficient)?


Elementary, my dear Watson. There is a HECK of a lot more to brake
pads than just the coefficient of friction - as Ihave been stating
time and time again. Steel on steel is noisy. Steel on steel has no
"feel". Steelon steel makes TERRIBLE brake dust, and steel on steel
would have terrible pad and rotor or shoe and drum life.

The coefficient of friction isn't all that bad - and the difference
between e and f, I would postulate, is not so "appreciable" as
"measurable"
and the difference in fade bertween ee and ff pads is laughable. At
600 degrees an ee can suffer from 0 to 25% fade, while the
"appreciably better" FF suffers from 0-22% fade - which means there is
EVERY possibility that an EE pad would hac WAY less fade than another
FF pad.

The STUPID thing is an fe can suffer 2-44% fade - doesn't make ANY
logical sense, but that's straight from
http://faculty.ccbcmd.edu/~smacadof/DOTPadCodes.htm



Friction material consists of a cobination of the following
components:
Fibers, such as fiberglass, kevlar, arimid, stainless steel, and
aluminum maintain the heat stability of the pad. These fibers have
various binding strengths and can be organic or metallic. Friction
Modifiers such as graphite adjust the friction level and fine tune the
performance characteristics of the pad at specific cold and hot
temperatures. Fillers take up dead space in the pad. These are
generally organic materials with some low frictional effect such as
sawdust. Finally, Resins are used to hold the elements of the pad
together so they don't crumble apart.

I puit more weight on the other qualities,as they are readilly evident
- while the friction grade of the material is not - as proven by the
tests.

I'm going to have to somewhat reluctantly agree with you, unless we get a
good reason, that no pad at all (i.e., just metal on metal) is "just as
good" and "maybe even better" than a high friction coefficient pad.

Pretty much that says "all pads work", does it not?

All pads work at least once. The life of the pads is not taken into
account

But how do you know that from the numbers printed on the pad?

You don't.

Again, I'm going to have to somewhat reluctantly agree with you, from a
logical standpoint, that if essentially no pad at all (i.e., an E
coefficient pad which has a coefficient of friction marginally better than
steel on steel) is better or about as good as having a pad, then almost
nothing printed on the side of the pad is going to make any difference.

Dropping a railway tie into a post hole will stop you faster than a
GG pad will = guaranteed!!!

Now another thing that affects HOT braking is the attachment of the
lining to the shoe/pad. Does the "glue" adequately transmit the heat
or act as an insulator?? Personally,I'm a BIG fan of rivetted linings
and pads, rather than bonded.

It seems there *must* be other *major* factors in braking performance,
other than the friction rating of the pads themselves.

That's a hard logical pill to swallow, for me, which is why I asked here,
hoping the s.e.r folks can enlighten us as to why.

Failure of the testing/certification process to reflect real world
conditions.

Well, the friction coefficient is a "real world" measurement.

Yes, but the assininely simple test procedure is FAR from "real
world". The behavior of a 1 square inchchunk of friction material does
not come CLOSE to the effect of 2 30 square inch arcs of pad material
in a 3 inch wide enclosed drum, or 2 10 square inch pads rubbing on an
open disk - simple things like pad vibration can reduce the EFFECTIVE
friction of a disc pad SIGNIFICANTLY (by cutting the "duty cycle" of
the pad basically in HALF (A vibrating pad is only in full contact
with the rotor roughly half the time)
An off-gassing pad only 1 inch square is not going to "float" on that
gas layer like a 10 square inch patch is under the same pressure. The
"micro-ball-bearings" of brake dust will have virtually no effect on a
1 inch piece of friction material, but may have a SIGNIFICANT effect
on 10 inches of brake shoe (which is why , partly, a grooved pad can
significantly outperform a solid pad.

There are WAY too many contributing factors that have WAY more
influence on brake performance than the relatively SMALL difference
between an e and an f pad. You could have an E pad at .34 and an f at
..36. You tell me there is a quantifiable difference between the
two????
Not in my world - where the rubber hits the road.

It just doesn't seem to matter in braking performance, based on that police
cruiser test I unearthed.

That's too bad, because it means you can't compare pads easily other than
to note the material, type, and manufacturer, which the DOT CODES printed
on each pad and shoe do tell you.

So at least we can tell three pads with three different marketing
strategies (e.g, Axxis, PBR, & Metal Masters) are the exact *same* pad, and
we can tell when a pad is rebranded (I think Centric only does rebranded
pads, for example, but I'd have to check the numbers to be sure).

Well over half of the "brands" are rebrands - not manufacturers.
particularly the "boutique" brands the enthusiasts and boy racers wet
their pants over

That indicates there is some utility in the mandated information that is
printed on the side of each pad.

VERY limited utility

But it's just sad that the friction coefficient means so little to a
friction material!

Sorry, but you engineers devise the tests. There is definitely
SOMETHING wrong with either the design of the test, the implementation
of the test, (application) or the theory applied.

Friction is friction.
It's a mathematical beast.

"Figures don't lie, but liars figure"
You can make math give you any answer you want - ask an accountant.

I don't think the SAE J866 Chase Tests lie about the friction of a 1"
square piece of the friction material.


They don't lie, they just, by their very nature, CAN NOT tell the
whole truth
They just don't predict real-world performance, it seems.
(As noted in the Police Cruiser report.)

Which is why I put very limited weight on the stamped/published
friction ratings.

Again, I must reluctantly agree with you, as hard a pill as it is to
swallow, that friction coefficients are NOT an important factor in the
performance of brake friction materials.

Sigh.

I just want to know WHY?

Because the initial friction co-efficient, as measured by the test in
question, is only one of a miriad factors involved in brake
performance - and a relatively MINOR one in the grand scheme of
things.

They have been proven time and again to be pretty close to useless.

Well, as I said, the *numbers* printed on the side of every pad/shoe sold
in the USA are *useful* in that they tell you the manufacturer, the
material, and, the friction rating - so even if we discount the friction
rating, it's nice to know when you can tell that two pads sold and marketed
at two different prices, are the same pad.

Now, if you take a, for instance, BRakebond pad with ee, another of
their pads with ef, and another eith ff - there MIGHT be a displayable
progression between them - all other factors being the same (which
they seldom are). Or you may find an ee or ef pad or shoe STILL
outperforms an ff in the real world.

I'm gonna have to reluctantly agree with you, yet again.
I don't ever dispute fact.

There is a lot more involved in brake performance - particularly hot
performance, than simple coefficent of friction.

It must be the case that friction isn't a *primary* determinant of brake
performance, hard a pill as that is to swallow.

In this case, the test using a one square inch sample of pad material
TOTALLY misses the mark - meaning the test design is faulty from the
start.

You'd think the SAE would know how to design a friction test though...

And as for not using EE friction materials - SOME of the cruisers
used in thase testa use ef or ff material in the
persuit special" vehicles, while civilian and even taxi (heavy duty)
use may have EE from the factory.

I know. I know. You don't have to rub it in.
I apologize for chastening you for using EE pads and shoes.

I still think my Toyota OEM shoes are FF so I'm gonna get FF.
Can you summarize again the short list of brands you'd recommend?
I want to do the work for the owner this weekend.

Thanks.


Well, if I was doing the job, I'd be heading over to my neighbourhood
NAPA store and pickingup a set of their Napa Ultra Premium rear shoe
kits for $57.28 CANADIAN (about $35 US??)and be done with it.
Or possibly over to Canadian Tire for a set of Brembos if they have
them 20% off (they did this week - but their coverage is limited -
they might not have shoes for a 'runner) or Wagners.

Let's face it - they are REAR brakes - and they do less than 30% of
the actual braking. A whole lot less in many cases due to the action
of the load sensing brake proportioning valve that cuts preasure to
the rear brakes when the rear axle us "unloaded" to prevent the rear
brakes from locking and the ABS from activating.

ABB (Brakebond) and Dana are generally predictable performers as
well.

On Thu, 11 Jan 2018 09:37:21 -0800 (PST),
wrote:

Differences in brake materials has have limited immediate consequences.
What will change is longevity, pad wear, visual effects, rotor wear,
noise, smell and other irrelevant consequences to the actual need.

With respect to "stopping distance", in the Michigan Police Cruiser study,
they controlled for identical deceleration (thus identical stopping
distance) and measured pedal force.

This is a different test than applying a uniform pedal force and measuring
stopping distance.
https://www.justnet.org/pdf/EvaluationBrakePads2000.pdf

I'm not sure how to extrapolate that information to stopping distances.

On Thu, 11 Jan 2018 13:20:56 -0800 (PST),
wrote:

a) Why would one want to interpret these codes in the first place?

Here's just one example to help answer that on-topic question
bearing in mind that brake pads are highly marketed items.

If you are comparing three pads that fit your vehicle spec:
a. $50 Axxis performance
b. $30 PBR midline
c. $20 Metal Masters economy

And you look at the code printed on the pads, you'll find they are
*exactly* the same numbers (since they're all the same pads/shoes, just
marketed differently).

In addition, the code printed on the pads tell you the material is exactly
the same, even if they're not the same pads (so you can more easily compare
across brands).

And it will tell you the coefficient of friction, even if those two things
are different still, so you can compare across lines and brands for
friction.

Why would you deny a vehicle owner that useful comparative information?
http://www.ameca.org/wp-content/uploads/2017/12/AMECA-List-of-VESC-V-3-Brake-Friction-Material-Edge-Codes-December-8-2017.pdf

On Thu, 11 Jan 2018 16:55:12 -0500,
Clare Snyder wrote:

Elementary, my dear Watson. There is a HECK of a lot more to brake
pads than just the coefficient of friction - as Ihave been stating
time and time again.

I found out the DOT Edge Code for the OE Toyota shoes which is
NBK LN508 FF
which is made by "Nisshinbo Automotive Manufacturing, Inc.".

It turns out that you were completely correct where I was hoping this
number would be a "holy grail" where I could use it to better compare two
brake shoes in my hands.

To get a better handle on how to interpret the numbers, I called the main
number at AMECA.ORG in Maryland at 202-898-0145 and spoke to the engineer
in charge of that "AMECA Edge Code Markings" cross reference.

It was a long discussion, the net of which is that this code isn't really
for the consumer.

The engineer said it's kind of like the so-called "serial number" on a
tire, or on a package of baked beans, where if something goes wrong, the
government has a way of tracking down whose fault it is. In addition, he
said that the SAE J866 Chase Test is really a quality metric, and not a
performance metric, even though friction is an outcome of the Chase Test.

The engineer did give me all sorts of personal insight into how to buy
brake pads but overall, he said you can't extrapolate very much real-world
decision-making data from the DOT Edge Code.

Of course, if you miraculously find two pads with the same DOT Edge Code,
then there's a 100% chance that it's the same friction material.

Or, if you find any pads with any of the 19 DOT edge codes that cross
reference to the same AMECA registration number 160426 then they too are
exactly the same friction material.
NAC D9011 FF
NAC LN508 FF
NAC N2009 FF
NBK D9011 FF
NBK LN508 FF ==== this is the OE Toyota brake shoes DOT edge code
NBK N2009 FF
NSA D9011 FF
NSA LN508 FF
NSA N2009 FF
NSC D9011 FF
NSC LN508 FF
NSC N2009 FF
SABC D9011 FF
SABC LN508 FF
SABC N2009 FF
SAC D9011 FF
SAC LN508 FF
SAC N2009 FF
SABC LN508 FF

That's because the AMECA registration number 160426 is for a specific
1-inch square piece of friction material that can be used on any brake pad
or shoe.

But that's really as far as a consumer can go with the edge code, he said.

He knew about all three of the Michigan police studies of EE and FF brake
pads, where those in-depth police cruiser tests also said it's hard to
extrapolate real-world performance from just the EE or FF friction code
they tested.

The AMECA engineer said that there are from 10 to 30 compounds in a brake
friction material, where he opined that Toyota spends enormous energy with
what he called the Tier 1 companies (e.g., Nisshinbo for Toyota) optimizing
the compound for each vehicle; but the engineer said that the aftermarket
suppliers (e.g, Centric, Wagner, Akebono, Axxis, etc.) centralize on about
a half dozen formulas for all their offerings.

In summary, the AMECA Edge Code is only "slightly" useful to a consumer, as
it tells the consumer the most information only if numbers match, but if
they don't match, the only three things it tells the consumer are the
manufacturer, the friction coefficient, and the registration number for the
specific friction material.

BTW, I was tempted to call the Nisshinbo senior principle engineer himself
(Tsuyoshi Kondo, +1-586-997-1000, ) who submitted
the 1-inch squares for our particular friction material on October 31st
2017 for repeat testing, but I didn't have the nerve to call him for more
information, especially after the AMECO engineer told me this information
is mostly for law enforcement and government use, and not really intended
for consumer use.

The one thing the AMECA engineer told me over and over again though, is
that what we'd want for comparative purposes, has been studied and studied
by the "smartest guys on the planet", and nobody can agree because of
conflicting interest.

So he sympathized with our needs.

On 13/01/2018 7:08 PM, Mad Roger wrote:
On Thu, 11 Jan 2018 16:55:12 -0500,
Clare Snyder wrote:

Elementary, my dear Watson. There is a HECK of a lot more to brake
pads than just the coefficient of friction - as Ihave been stating
time and time again.

I found out the DOT Edge Code for the OE Toyota shoes which is
NBK LN508 FF
which is made by "Nisshinbo Automotive Manufacturing, Inc.".

It turns out that you were completely correct where I was hoping this
number would be a "holy grail" where I could use it to better compare two
brake shoes in my hands.

To get a better handle on how to interpret the numbers, I called the main
number at AMECA.ORG in Maryland at 202-898-0145 and spoke to the engineer
in charge of that "AMECA Edge Code Markings" cross reference.

It was a long discussion, the net of which is that this code isn't really
for the consumer.

The engineer said it's kind of like the so-called "serial number" on a
tire, or on a package of baked beans, where if something goes wrong, the
government has a way of tracking down whose fault it is. In addition, he
said that the SAE J866 Chase Test is really a quality metric, and not a
performance metric, even though friction is an outcome of the Chase Test.

The engineer did give me all sorts of personal insight into how to buy
brake pads but overall, he said you can't extrapolate very much real-world
decision-making data from the DOT Edge Code.

Of course, if you miraculously find two pads with the same DOT Edge Code,
then there's a 100% chance that it's the same friction material.

Or, if you find any pads with any of the 19 DOT edge codes that cross
reference to the same AMECA registration number 160426 then they too are
exactly the same friction material.
NAC D9011 FF
NAC LN508 FF
NAC N2009 FF
NBK D9011 FF
NBK LN508 FF ==== this is the OE Toyota brake shoes DOT edge code
NBK N2009 FF
NSA D9011 FF
NSA LN508 FF
NSA N2009 FF
NSC D9011 FF
NSC LN508 FF
NSC N2009 FF
SABC D9011 FF
SABC LN508 FF
SABC N2009 FF
SAC D9011 FF
SAC LN508 FF
SAC N2009 FF
SABC LN508 FF

That's because the AMECA registration number 160426 is for a specific
1-inch square piece of friction material that can be used on any brake pad
or shoe.

But that's really as far as a consumer can go with the edge code, he said.

He knew about all three of the Michigan police studies of EE and FF brake
pads, where those in-depth police cruiser tests also said it's hard to
extrapolate real-world performance from just the EE or FF friction code
they tested.

The AMECA engineer said that there are from 10 to 30 compounds in a brake
friction material, where he opined that Toyota spends enormous energy with
what he called the Tier 1 companies (e.g., Nisshinbo for Toyota) optimizing
the compound for each vehicle; but the engineer said that the aftermarket
suppliers (e.g, Centric, Wagner, Akebono, Axxis, etc.) centralize on about
a half dozen formulas for all their offerings.

In summary, the AMECA Edge Code is only "slightly" useful to a consumer, as
it tells the consumer the most information only if numbers match, but if
they don't match, the only three things it tells the consumer are the
manufacturer, the friction coefficient, and the registration number for the
specific friction material.

BTW, I was tempted to call the Nisshinbo senior principle engineer himself
(Tsuyoshi Kondo, +1-586-997-1000, ) who submitted
the 1-inch squares for our particular friction material on October 31st
2017 for repeat testing, but I didn't have the nerve to call him for more
information, especially after the AMECO engineer told me this information
is mostly for law enforcement and government use, and not really intended
for consumer use.

The one thing the AMECA engineer told me over and over again though, is
that what we'd want for comparative purposes, has been studied and studied
by the "smartest guys on the planet", and nobody can agree because of
conflicting interest.

So he sympathized with our needs.

All the while thinking, "*Who is this nutcase?*".

--

Xeno

On Sat, 13 Jan 2018 22:45:47 +1100,
Xeno wrote:

All the while thinking, "*Who is this nutcase?*".

Xeno the troll.

How much on-topic technical value have you added to *any* thread.

In your *entire* life?

Zero!

Why?

Xeno the troll can't comprehend the topic.
Nor can Xeno the troll add any technical value.

Why?

Xeno the troll is too stupid to add any value to any topic whatsoever.

Just watch. Xeno the troll proves he's incapable of even *comprehending*
the technical topic by his every response.

Xeno the troll will respond with more non-technical worthless blather.
Just watch.

On 2018-01-11 06:46, Mad Roger wrote:
I agree that there are *many* factors in the act of slowing down a vehicle
with brake friction material heating up causing a loss of the energy of
momentum.


Bollox bollox bollox.

Momentum and energy are quite different quantities, if you want to play
properly at being a scientist.

On 2018-01-11 12:09, Mad Roger wrote:

It seems there *must* be other *major* factors in braking performance,
other than the friction rating of the pads themselves.

That's a hard logical pill to swallow, for me, which is why I asked here,
hoping the s.e.r folks can enlighten us as to why.


Whats the stupid fixation with the coefficient of friction anyway?

As any fule kno, friction is notionally independent of contact area, and
force due to friction is determined by the coefficient of friction *and
the applied force* so if you want more frictional force, you just need
to press the pedal harder, or have more servo assistance.

Simply ignoring all of the other (engineering) considerations which have
been cited, relating to brake performance in the real world, will not
help you be enlightened about anything. It just makes you look like a
dumb **** trying to be cleverer than your brain permits.

On Sat, 13 Jan 2018 08:08:03 -0000 (UTC), Mad Roger
wrote:

On Thu, 11 Jan 2018 16:55:12 -0500,
Clare Snyder wrote:

Elementary, my dear Watson. There is a HECK of a lot more to brake
pads than just the coefficient of friction - as Ihave been stating
time and time again.

I found out the DOT Edge Code for the OE Toyota shoes which is
NBK LN508 FF
which is made by "Nisshinbo Automotive Manufacturing, Inc.".

It turns out that you were completely correct where I was hoping this
number would be a "holy grail" where I could use it to better compare two
brake shoes in my hands.

To get a better handle on how to interpret the numbers, I called the main
number at AMECA.ORG in Maryland at 202-898-0145 and spoke to the engineer
in charge of that "AMECA Edge Code Markings" cross reference.

It was a long discussion, the net of which is that this code isn't really
for the consumer.

The engineer said it's kind of like the so-called "serial number" on a
tire, or on a package of baked beans, where if something goes wrong, the
government has a way of tracking down whose fault it is. In addition, he
said that the SAE J866 Chase Test is really a quality metric, and not a
performance metric, even though friction is an outcome of the Chase Test.

The engineer did give me all sorts of personal insight into how to buy
brake pads but overall, he said you can't extrapolate very much real-world
decision-making data from the DOT Edge Code.

Of course, if you miraculously find two pads with the same DOT Edge Code,
then there's a 100% chance that it's the same friction material.


UNLESS it's counterfeit (admitedly likely less than 1% chance -
until it is - - - -

Or, if you find any pads with any of the 19 DOT edge codes that cross
reference to the same AMECA registration number 160426 then they too are
exactly the same friction material.
NAC D9011 FF
NAC LN508 FF
NAC N2009 FF
NBK D9011 FF
NBK LN508 FF ==== this is the OE Toyota brake shoes DOT edge code
NBK N2009 FF
NSA D9011 FF
NSA LN508 FF
NSA N2009 FF
NSC D9011 FF
NSC LN508 FF
NSC N2009 FF
SABC D9011 FF
SABC LN508 FF
SABC N2009 FF
SAC D9011 FF
SAC LN508 FF
SAC N2009 FF
SABC LN508 FF

That's because the AMECA registration number 160426 is for a specific
1-inch square piece of friction material that can be used on any brake pad
or shoe.

But that's really as far as a consumer can go with the edge code, he said.

He knew about all three of the Michigan police studies of EE and FF brake
pads, where those in-depth police cruiser tests also said it's hard to
extrapolate real-world performance from just the EE or FF friction code
they tested.

The AMECA engineer said that there are from 10 to 30 compounds in a brake
friction material, where he opined that Toyota spends enormous energy with
what he called the Tier 1 companies (e.g., Nisshinbo for Toyota) optimizing
the compound for each vehicle; but the engineer said that the aftermarket
suppliers (e.g, Centric, Wagner, Akebono, Axxis, etc.) centralize on about
a half dozen formulas for all their offerings.

In summary, the AMECA Edge Code is only "slightly" useful to a consumer, as
it tells the consumer the most information only if numbers match, but if
they don't match, the only three things it tells the consumer are the
manufacturer, the friction coefficient, and the registration number for the
specific friction material.

BTW, I was tempted to call the Nisshinbo senior principle engineer himself
(Tsuyoshi Kondo, +1-586-997-1000, ) who submitted
the 1-inch squares for our particular friction material on October 31st
2017 for repeat testing, but I didn't have the nerve to call him for more
information, especially after the AMECO engineer told me this information
is mostly for law enforcement and government use, and not really intended
for consumer use.

The one thing the AMECA engineer told me over and over again though, is
that what we'd want for comparative purposes, has been studied and studied
by the "smartest guys on the planet", and nobody can agree because of
conflicting interest.

So he sympathized with our needs.

On Sat, 13 Jan 2018 12:39:51 -0800, Mary-Jane Rottencrotch
wrote:

On 2018-01-11 12:09, Mad Roger wrote:

It seems there *must* be other *major* factors in braking performance,
other than the friction rating of the pads themselves.

That's a hard logical pill to swallow, for me, which is why I asked here,
hoping the s.e.r folks can enlighten us as to why.


Whats the stupid fixation with the coefficient of friction anyway?

As any fule kno, friction is notionally independent of contact area, and
force due to friction is determined by the coefficient of friction *and
the applied force* so if you want more frictional force, you just need
to press the pedal harder, or have more servo assistance.

Simply ignoring all of the other (engineering) considerations which have
been cited, relating to brake performance in the real world, will not
help you be enlightened about anything. It just makes you look like a
dumb **** trying to be cleverer than your brain permits.


I guess we'll have to give the poor guy a break. I suspect he is a
young graduate engineer who has yet to learn how little he knows.

On 01/13/2018 12:39 PM, Mary-Jane Rottencrotch wrote:
On 2018-01-11 12:09, Mad Roger wrote:

It seems there *must* be other *major* factors in braking performance,
other than the friction rating of the pads themselves.

That's a hard logical pill to swallow, for me, which is why I asked here,
hoping the s.e.r folks can enlighten us as to why.

Whats the stupid fixation with the coefficient of friction anyway?

As any fule kno, friction is notionally independent of contact area, and
force due to friction is determined by the coefficient of friction *and
the applied force* so if you want more frictional force, you just need
to press the pedal harder, or have more servo assistance.

Yu kleerly paid atenshun to Sigismund the Mad Maths Master! Matron
would be pleesed.

--
Cheers, Bev
"What fresh hell is this?" -- Dorothy Parker

On Sun, 14 Jan 2018 01:30:23 -0800 (PST),
wrote:

I'm not sure how to extrapolate that information to stopping distances.

I would have thought that as long as the driver & brake servo can
apply enough force it would make no difference at all to stopping
distances.

Thanks for that observation as I'm trying to derive as much real-world
benefit from the police cruiser report as is possible given Clare's astute
observations about EE and FF pads faring differently, but not because of
their coefficient of friction.

There were 3 police tests over the decade, where only the penultimate test
aimed for uniform pedal pressure.
1. https://www.justnet.org/pdf/BRAKEPAD.PDF
2. https://www.justnet.org/pdf/EvaluationBrakePads2000.pdf
3. https://www.justnet.org/pdf/Copy-of-...port-Draft.pdf


The middle test is the one that aimed for a given pedal pressu
a. 45-to-15mph at 10ft/s/s (approximately ~10 foot pounds +- a few)
b. 70-to-30mph at 22ft/s/s (approximately ~20 foot pounds +- a few)
c. 90-to-0mph at 22ft/s/s (approximately ~30 foot pounds +- a few)

Fundamentally, they said pedal pressure is, effectively, what a human does
all day every day - hence pedal pressure is, arguably, more important in a
well-used "cruising" vehicle that doesn't do panic stops consistently.

A targeted deceleration rate where pedal force is proportional to pad temp.

The other two studies were different.
1. Mostly stopping distance
2. Mostly pedal pressure
3. Mostly driver perception

In the end, the DOT edge code (AMECA edge code) is only slightly useful to
a consumer, I think. I wish it were more useful, but I've gleaned out of it
what I can, and that's the best any of us can hope to do.

I was hoping to get more insight from the scientific and mechanical folks
here.

On 1/14/18 10:37 AM, Mad Roger wrote:
I was hoping to get more insight from the scientific and
mechanical folks here.

Ain't gonna happen.
The people what know how this **** works aren't going to
waste their time arguing with your preconceived misconceptions.


--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

On Sun, 14 Jan 2018 01:27:58 -0800 (PST),
wrote:

The real question who in the hell ****ing cares??

I didn't, until I found the brake pads fitted by a quick nationwide chain a year earlier were totally disintegrating.

Funny thing is you can get the same brake pads at a scrapyard for a fraction the price, but no-one wants to.

It's a valid question of who cares about choosing the proper brake pads.

Bear in mind that the Toyota FF pads are $157 a set at the local
dealership, while at a local parts store, I can get FF pads for $20 a set.

C = Up to 0.15u
E = 0.15u to 0.25u
E = 0.25u to 0.35u
F = 0.35u to 0.45u
G = 0.45u to 0.55u
H = 0.55u to 0.65u
Z = Unclassified

That's a huge difference in price, for material that has the same friction
coefficient, if not quality, don't you think?

So it behooves intelligent people to figure out, scientifically, whether
there is a way to tell what's *different* about those pads.

Everyone understands a number line, but there are non-linear issues here
which nobody here seems (so far) to understand such that they can tell us
how to properly compare the two brake pads based on the information a
consumer would have.

In the end, I don't see any indication whatsoever that anyone here knows
how to properly compare the performance of those $157 and $20 brake pads
and shoes in order to make an intelligent buying decision.

That's kind of a sad revelation for this newsgroup, don't you think?

On Sun, 14 Jan 2018 18:20:33 -0000 (UTC), Mad Roger
wrote:

On Sun, 14 Jan 2018 01:27:58 -0800 (PST),
wrote:

The real question who in the hell ****ing cares??

I didn't, until I found the brake pads fitted by a quick nationwide chain a year earlier were totally disintegrating.

Funny thing is you can get the same brake pads at a scrapyard for a fraction the price, but no-one wants to.

It's a valid question of who cares about choosing the proper brake pads.

Bear in mind that the Toyota FF pads are $157 a set at the local
dealership, while at a local parts store, I can get FF pads for $20 a set.

C = Up to 0.15u
E = 0.15u to 0.25u
E = 0.25u to 0.35u
F = 0.35u to 0.45u
G = 0.45u to 0.55u
H = 0.55u to 0.65u
Z = Unclassified

That's a huge difference in price, for material that has the same friction
coefficient, if not quality, don't you think?

So it behooves intelligent people to figure out, scientifically, whether
there is a way to tell what's *different* about those pads.

Everyone understands a number line, but there are non-linear issues here
which nobody here seems (so far) to understand such that they can tell us
how to properly compare the two brake pads based on the information a
consumer would have.

In the end, I don't see any indication whatsoever that anyone here knows
how to properly compare the performance of those $157 and $20 brake pads
and shoes in order to make an intelligent buying decision.

That's kind of a sad revelation for this newsgroup, don't you think?


Not at all. Even a "brake engineer" would not be able to tell ypou
how to tell the good fromthe bad (or less good - don't knowthere is
any "bad"brakes on the market - even a lot of the "counterfeit" stuff
will stop the car). The "brake engineer" would likely beable to tell
you which of "his" product is better - but not necessarily if his was
betteror worse than another brand.

Back when I was a Toyota tech and service manager there were at least
2 different formulationsof brake pad that fit numerous Toyota vehicles
of the time - one was used up to a particular production date, and
another after. Both were available as replacement parts, and I always
used the one, regardless of vehicle production date, because it
stopped better and I could install the second and third set without
having to replace rotors. It was a difference between the metal used
in the "semi metallic" lining. One was magnetic - the other had brass
in it. The brass stopped better and didn't cause pitting of the
rotors. The pads didn't last as long, but virtually nobody ever
actually wore out the "magnetic" ones before the rotors needed
replacing, so the pad life, in and of itself, was a total non-issue.
IIRC the brass was the early pad and the iron was the
replacement/update.

The same situation rose years back on, I believe, FORD brake shoes
where the linings would deteriorate and fall apart before the half
wear point. They went from rivetted to bonded, and then the glue
started letting go, and the entire lining would free-wheel between the
shoes and the drum. It was a real bugger if that happened only on one
front wheel. It would have a MONSTEWROUS pull one time, then brake
fine the next - and you NEVER knew when it was going to pull - or
which way - because sometimes the loose material would grab, sometimes
it would hold properly, andothertimes it would do virtually nothing -
- -

Brake materials are a fine line between a science and a "black art"

On Sun, 14 Jan 2018 14:46:53 -0500,
Clare Snyder wrote:

In the end, I don't see any indication whatsoever that anyone here knows
how to properly compare the performance of those $157 and $20 brake pads
and shoes in order to make an intelligent buying decision.

That's kind of a sad revelation for this newsgroup, don't you think?

Not at all. Even a "brake engineer" would not be able to tell ypou
how to tell the good fromthe bad (or less good - don't knowthere is
any "bad"brakes on the market - even a lot of the "counterfeit" stuff
will stop the car).

Hi Clare,
You're actually the *only* one on any of these three newsgroups who knew
the bottom line from the start, which is that we're ****ed when we try to
compare a $157 brake pad with a $20 brake pad.

Everyone loves a number line, which is why people buy batteries by warranty
or why they say the stupid line that "you get what you pay for" when we all
know that a $300 set of speakers at Toyota gets you a crappy speaker
compared to a $50 set at Crutchfields.

So you can never tell by price. You can only tell by quality.
And there's no way to *compare* quality, it seems.

You knew that. Which is why you stick to name brands. Which is fine, as
name brands is just another way of saying you buy by a number line, where
the number line only has parts on the right and left of zero.

Brands to the right of zero you'd buy (e.g., Napa or Wagner) and brands to
the left you wouldn't buy.

But that sucks too as a determinant although at least with the DOT Edge
Code, we can tell, for sure, which company made the friction material (so
we could tell that an Axxis pad is the same as a PBR which is the same as a
Metal Masters pad, for example).

The "brake engineer" would likely beable to tell
you which of "his" product is better - but not necessarily if his was
betteror worse than another brand.

Yes. That's what the AMECA engineer basically said. He even said, many
times, that the brake engineer might not even know himself, unless he
himself submitted the pad material for testing.

So, basically EVERYONE is buying brake pads completely blind.

If that's not sad to you, it is to me.

Back when I was a Toyota tech and service manager there were at least
2 different formulationsof brake pad that fit numerous Toyota vehicles
of the time - one was used up to a particular production date, and
another after. Both were available as replacement parts, and I always
used the one, regardless of vehicle production date, because it
stopped better and I could install the second and third set without
having to replace rotors. It was a difference between the metal used
in the "semi metallic" lining. One was magnetic - the other had brass
in it.

If you have the DOT Edge Code, we could tell at least who made each
friction material, and whether they're on other pads, and whether they
truly were the same or not, and what the friction coefficients were.

But that's about it for what we could tell about the two pads from just
having them both in our hands.

That's sad.

The brass stopped better and didn't cause pitting of the
rotors. The pads didn't last as long, but virtually nobody ever
actually wore out the "magnetic" ones before the rotors needed
replacing, so the pad life, in and of itself, was a total non-issue.
IIRC the brass was the early pad and the iron was the
replacement/update.

I don't even look at the marketing bull**** because one spec of dust and
they can call it ceramic. There's no law or rules. They can put a spec of
iron and then call it semi metallic.

The only laws are they can't put asbestos in it.

The rest is marketing bull****. We've been there, so let's not go there
again.

We're essentially choosing brake pads almost completely blind.
And that's sad.

The same situation rose years back on, I believe, FORD brake shoes
where the linings would deteriorate and fall apart before the half
wear point. They went from rivetted to bonded, and then the glue
started letting go, and the entire lining would free-wheel between the
shoes and the drum.

Yes. I'm not covering defects in workmanship or design of the backing.
I'm just covering the friction material here, because friction is the
fundamental thing a brake pad does.

I know all about the issues that we will never be able to compare pads with
such as longevity of the pads and rotors, fitment, noise, dusting, etc.

Brake materials are a fine line between a science and a "black art"

I agree that for the *formulator*, it's likely halfway between science and
a black art, but for the poor consumer, it's complete marketing bull****.

Nobody, it appears, actually knows anything about buying brake pads when
they have two pads they've never seen before in their hands.

You have the EXPERIENCE to pick a pad, but even if I shoved two pads that
you have never seen before (such as two I'm going to need to compare), you
can't compare them either (unless you know the brand).

Even then, you harp on the conterfeits, so unless you know a telltale sign,
you can't tell from the brand either, especially when buying online.

SO it's just sad, sad, sad, that we're all utterly blind when it comes to
comparing brake pads. I think that's very depressing. We're at the mercy of
marketing bull****ters and idiots who do brake pad reviews on amazon that
make no sense and aren't for the same car and compare things like worn old
pads against brand new pads, and the butt dyno takes over from there.

All those reviews are basically worthless.
All the marketing bull**** is basically worthless.

The one dream I had was that this AMECA Edge Code could tell me a lot, and
it does tell me three things, but that's it.

Sigh. It's just sad.

I do thank you for your help, as you're the only one, I think, who knew
what he was talking about from the start. I had to learn it. You already
knew it.

On 1/14/2018 5:11 PM, Mad Roger wrote:
On Sun, 14 Jan 2018 14:46:53 -0500,
Clare Snyder wrote:

In the end, I don't see any indication whatsoever that anyone here knows
how to properly compare the performance of those $157 and $20 brake pads
and shoes in order to make an intelligent buying decision.

That's kind of a sad revelation for this newsgroup, don't you think?

Not at all. Even a "brake engineer" would not be able to tell ypou
how to tell the good fromthe bad (or less good - don't knowthere is
any "bad"brakes on the market - even a lot of the "counterfeit" stuff
will stop the car).

Hi Clare,
You're actually the *only* one on any of these three newsgroups who knew
the bottom line from the start, which is that we're ****ed when we try to
compare a $157 brake pad with a $20 brake pad.

Everyone loves a number line, which is why people buy batteries by warranty
or why they say the stupid line that "you get what you pay for" when we all
know that a $300 set of speakers at Toyota gets you a crappy speaker
compared to a $50 set at Crutchfields.

So you can never tell by price. You can only tell by quality.
And there's no way to *compare* quality, it seems.

You knew that. Which is why you stick to name brands. Which is fine, as
name brands is just another way of saying you buy by a number line, where
the number line only has parts on the right and left of zero.

Brands to the right of zero you'd buy (e.g., Napa or Wagner) and brands to
the left you wouldn't buy.

But that sucks too as a determinant although at least with the DOT Edge
Code, we can tell, for sure, which company made the friction material (so
we could tell that an Axxis pad is the same as a PBR which is the same as a
Metal Masters pad, for example).

The "brake engineer" would likely beable to tell
you which of "his" product is better - but not necessarily if his was
betteror worse than another brand.

Yes. That's what the AMECA engineer basically said. He even said, many
times, that the brake engineer might not even know himself, unless he
himself submitted the pad material for testing.

So, basically EVERYONE is buying brake pads completely blind.

If that's not sad to you, it is to me.

Back when I was a Toyota tech and service manager there were at least
2 different formulationsof brake pad that fit numerous Toyota vehicles
of the time - one was used up to a particular production date, and
another after. Both were available as replacement parts, and I always
used the one, regardless of vehicle production date, because it
stopped better and I could install the second and third set without
having to replace rotors. It was a difference between the metal used
in the "semi metallic" lining. One was magnetic - the other had brass
in it.

If you have the DOT Edge Code, we could tell at least who made each
friction material, and whether they're on other pads, and whether they
truly were the same or not, and what the friction coefficients were.

But that's about it for what we could tell about the two pads from just
having them both in our hands.

That's sad.

The brass stopped better and didn't cause pitting of the
rotors. The pads didn't last as long, but virtually nobody ever
actually wore out the "magnetic" ones before the rotors needed
replacing, so the pad life, in and of itself, was a total non-issue.
IIRC the brass was the early pad and the iron was the
replacement/update.

I don't even look at the marketing bull**** because one spec of dust and
they can call it ceramic. There's no law or rules. They can put a spec of
iron and then call it semi metallic.

The only laws are they can't put asbestos in it.

The rest is marketing bull****. We've been there, so let's not go there
again.

We're essentially choosing brake pads almost completely blind.
And that's sad.

The same situation rose years back on, I believe, FORD brake shoes
where the linings would deteriorate and fall apart before the half
wear point. They went from rivetted to bonded, and then the glue
started letting go, and the entire lining would free-wheel between the
shoes and the drum.

Yes. I'm not covering defects in workmanship or design of the backing.
I'm just covering the friction material here, because friction is the
fundamental thing a brake pad does.

I know all about the issues that we will never be able to compare pads with
such as longevity of the pads and rotors, fitment, noise, dusting, etc.

Brake materials are a fine line between a science and a "black art"

I agree that for the *formulator*, it's likely halfway between science and
a black art, but for the poor consumer, it's complete marketing bull****.

Nobody, it appears, actually knows anything about buying brake pads when
they have two pads they've never seen before in their hands.

You have the EXPERIENCE to pick a pad, but even if I shoved two pads that
you have never seen before (such as two I'm going to need to compare), you
can't compare them either (unless you know the brand).

Even then, you harp on the conterfeits, so unless you know a telltale sign,
you can't tell from the brand either, especially when buying online.

SO it's just sad, sad, sad, that we're all utterly blind when it comes to
comparing brake pads. I think that's very depressing. We're at the mercy of
marketing bull****ters and idiots who do brake pad reviews on amazon that
make no sense and aren't for the same car and compare things like worn old
pads against brand new pads, and the butt dyno takes over from there.

All those reviews are basically worthless.
All the marketing bull**** is basically worthless.

The one dream I had was that this AMECA Edge Code could tell me a lot, and
it does tell me three things, but that's it.

Sigh. It's just sad.

I do thank you for your help, as you're the only one, I think, who knew
what he was talking about from the start. I had to learn it. You already
knew it.


And all that is different from buying a bag of white flour
to make cookies in what way exactly?

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On Sun, 14 Jan 2018 23:11:16 -0000 (UTC), Mad Roger
wrote:

On Sun, 14 Jan 2018 14:46:53 -0500,
Clare Snyder wrote:

In the end, I don't see any indication whatsoever that anyone here knows
how to properly compare the performance of those $157 and $20 brake pads
and shoes in order to make an intelligent buying decision.

That's kind of a sad revelation for this newsgroup, don't you think?

Not at all. Even a "brake engineer" would not be able to tell ypou
how to tell the good fromthe bad (or less good - don't knowthere is
any "bad"brakes on the market - even a lot of the "counterfeit" stuff
will stop the car).

Hi Clare,
You're actually the *only* one on any of these three newsgroups who knew
the bottom line from the start, which is that we're ****ed when we try to
compare a $157 brake pad with a $20 brake pad.

Everyone loves a number line, which is why people buy batteries by warranty
or why they say the stupid line that "you get what you pay for" when we all
know that a $300 set of speakers at Toyota gets you a crappy speaker
compared to a $50 set at Crutchfields.

So you can never tell by price. You can only tell by quality.
And there's no way to *compare* quality, it seems.

You knew that. Which is why you stick to name brands. Which is fine, as
name brands is just another way of saying you buy by a number line, where
the number line only has parts on the right and left of zero.

Brands to the right of zero you'd buy (e.g., Napa or Wagner) and brands to
the left you wouldn't buy.

But that sucks too as a determinant although at least with the DOT Edge
Code, we can tell, for sure, which company made the friction material (so
we could tell that an Axxis pad is the same as a PBR which is the same as a
Metal Masters pad, for example).

The "brake engineer" would likely beable to tell
you which of "his" product is better - but not necessarily if his was
betteror worse than another brand.

Yes. That's what the AMECA engineer basically said. He even said, many
times, that the brake engineer might not even know himself, unless he
himself submitted the pad material for testing.

So, basically EVERYONE is buying brake pads completely blind.

If that's not sad to you, it is to me.

Back when I was a Toyota tech and service manager there were at least
2 different formulationsof brake pad that fit numerous Toyota vehicles
of the time - one was used up to a particular production date, and
another after. Both were available as replacement parts, and I always
used the one, regardless of vehicle production date, because it
stopped better and I could install the second and third set without
having to replace rotors. It was a difference between the metal used
in the "semi metallic" lining. One was magnetic - the other had brass
in it.

If you have the DOT Edge Code, we could tell at least who made each
friction material, and whether they're on other pads, and whether they
truly were the same or not, and what the friction coefficients were.

But that's about it for what we could tell about the two pads from just
having them both in our hands.

That's sad.

The brass stopped better and didn't cause pitting of the
rotors. The pads didn't last as long, but virtually nobody ever
actually wore out the "magnetic" ones before the rotors needed
replacing, so the pad life, in and of itself, was a total non-issue.
IIRC the brass was the early pad and the iron was the
replacement/update.

I don't even look at the marketing bull**** because one spec of dust and
they can call it ceramic. There's no law or rules. They can put a spec of
iron and then call it semi metallic.

The only laws are they can't put asbestos in it.

The rest is marketing bull****. We've been there, so let's not go there
again.

We're essentially choosing brake pads almost completely blind.
And that's sad.

The same situation rose years back on, I believe, FORD brake shoes
where the linings would deteriorate and fall apart before the half
wear point. They went from rivetted to bonded, and then the glue
started letting go, and the entire lining would free-wheel between the
shoes and the drum.

Yes. I'm not covering defects in workmanship or design of the backing.
I'm just covering the friction material here, because friction is the
fundamental thing a brake pad does.



N o, the PRIMARY quality of a brake material that YOU need to worry
about is "performance"
That "performance" includes how well it stops hot and cold, brake
feel, pad life, and rotor life.

The coefficient of friction only affects ONE of those qualities - and
the gross difference between a good e and a poor g is NEGLIGIBLE .
(Both are essentially an F -)

AN OEM GUALITY brake part will be CLOSE to what was specified by the
manufacturer - may be marginally better or marginally worse - but they
will be close.

I talk to my jobber and ask what their warranty experience is with
different products. If they have noise complaints, or poor wear, on
one brand/model but not on another, I stay away from the one that has
problems.

Years ago I got and read the Service Station and Garage Management
magazine - which had articles about different products - written by
mechanics, not engineers and salemen, reporting both the Gems and the
Stinkers.

I know all about the issues that we will never be able to compare pads with
such as longevity of the pads and rotors, fitment, noise, dusting, etc.

Brake materials are a fine line between a science and a "black art"

I agree that for the *formulator*, it's likely halfway between science and
a black art, but for the poor consumer, it's complete marketing bull****.

Look for a certified label





New vehicles must meet federal performance standards—a minimum
stopping distance in a variety of situations under a specified pedal
effort. Many consumers assume all aftermarket replacement pads will
perform just as well or better than factory parts, but that's not
necessarily the case.

In an effort to improve the customer's comfort level—and also to avoid
future government regulations—brake manufacturers can test and verify
their products under two voluntary certification standards. Both are
designed to ensure that replacement brakes are as effective as
original equipment, and consumers should make sure that any pads being
installed on their vehicle are certified.

The first is an independent proprietary program developed by Greening
Testing Laboratories in Detroit called D3EA—which stands for Dual
Dynamometer Differential Effectiveness Analysis. This procedure tests
front and rear friction materials together on dual dynamometers, then
simulates vehicle weight and speed through a computer program to
measure braking effectiveness and balance for different applications.
D3EA was introduced in 1996, and among the first aftermarket companies
to achieve D3EA certification were ACDelco, NAPA, Raybestos, and
Satisfied.

The Brake Manufacturers Council (BMC) has a second certification
standard called BEEP, or Brake Effectiveness Evaluation Procedure.
BEEP testing is conducted on a single dynamometer, and the numbers are
washed through a computer program to compare brake performance with
federal standards for new vehicles. The BEEP approval seals appear on
packaging as manufacturers submit products for certification.

The D3EA tests are proprietary and more expensive, but they're also
completely independent and tougher to pass. Brake manufacturers have
contended that most consumers change only the front or rear brakes at
one time, so a concurrent dual test is unnecessary. But, according to
officials from Greening, NHTSA tests in the 1980s concluded there was
a significant reduction in braking performance when there was a
differential between front and rear replacement pads as compared with
original factory parts. That report provided some of the motivation
for the brake industry to begin seeking a certification standard
before the federal government issued regulations for replacement pads.
The obvious concern over BEEP testing is that the manufacturers
themselves oversaw the development of the certification standards.
While the program received input from the Society of Automotive
Engineers and actual certification is currently conducted at an
independent laboratory, BMC members can conduct similar tests on their
own single dynamometers and compute the numbers.

Consumers must remember that not all of an aftermarket manufacturer's
lineup gets certified, only pads designed for a specific vehicle that
passed the designated test. Also, since the D3EA tests are expensive,
manufacturers may test just the standard line for a particular
vehicle. One can assume then that any upgraded line from that same
manufacturer will meet the test standards. That's why heavy duty or
the new ceramic pads may not carry the seal. The best advice is to
look for manufacturers that aggressively test their standard line,
then move up in grade if you need more performance or seek other
advantages such as minimal wheel dust.



Nobody, it appears, actually knows anything about buying brake pads when
they have two pads they've never seen before in their hands.

You have the EXPERIENCE to pick a pad, but even if I shoved two pads that
you have never seen before (such as two I'm going to need to compare), you
can't compare them either (unless you know the brand).

Even then, you harp on the conterfeits, so unless you know a telltale sign,
you can't tell from the brand either, especially when buying online.

Which is why I seldom buy stuff like that online - and if I do, I buy
from a vendor I KNOW is honest and reliable. (I'll sometimes order
parts from Napa Onlineand pick them ujp at my local napa store -
particularly if I find I need something on the weekend when the store
is not open and I want it for Monday)

SO it's just sad, sad, sad, that we're all utterly blind when it comes to
comparing brake pads. I think that's very depressing. We're at the mercy of
marketing bull****ters and idiots who do brake pad reviews on amazon that
make no sense and aren't for the same car and compare things like worn old
pads against brand new pads, and the butt dyno takes over from there.

Then pay the extra and buy the Toyota parts - that way YOU KNOW what
you are buying. Sometimes peace of mind costs a few bucks.

All those reviews are basically worthless.
All the marketing bull**** is basically worthless.

Any review by DIY guys on places liike Amazon are generally worse
than useless.

The one dream I had was that this AMECA Edge Code could tell me a lot, and
it does tell me three things, but that's it.

Sigh. It's just sad.

Buy D3EA certified parts and you stand a much higher than normal
chance of getting what you need.

I do thank you for your help, as you're the only one, I think, who knew
what he was talking about from the start. I had to learn it. You already
knew it.

On Sun, 14 Jan 2018 17:58:04 -0800 (PST),
wrote:

That's retail.

That's why I say those who say "you get what you pay for" are misguided
because a $157 pad "might" be just as good or bad as a $20 pad, where I can
prove this statement for the $300 20W Panasonic speakers in a Toyota since
I know the specs on the $50 speakers at Crutchfields.

Even at Crutchfields, you can get a good $50 speaker or a less-good $50
speaker, and the price is exactly the same.

So if someone tells me "you get what you pay for", they'll get the same
rant from me that everyone loves to pick products off a number line, but
the real number line is a bunch of specs, and not a simple price.

That's retail for you!

And really the difference is greater, I once bought a set of 4 brake
shoes for +AKM-1, that's under $2. They performed without any issue. Why?

I think price is not an indication of anything other than what the
marketing can make people pay. It's certainly not an indication of quality.

No-one here wants to buy brake parts from scrapyards, even though
they're the same parts you get in the shops.

I'm not sure what you mean by "scrapyards". To me, that means a junk yard,
which contains dead cars. I wouldn't buy brakes off a dead car for a
billion reasons which are obvious so I shouldn't need to state it.

What's the difference between my concept of a junkyard (which contains
entire cars that were thrown away) and your scrapyard?

Are you talking about *used* brake pads or *new* brake pads?

if both do the job ok, $20 is the intelligent buying decision.

There is no other logical conclusion to be made, given the information we
have. Price is NOT the determinant of a good or bad brake pad.

The sad thing is that there is no determinant we can make that will hold
true other than there is no difference practically that you can do anything
about.

I'm NOT saying they are all the same. I'm saying we consumers can't tell by
having two of them in our hand or having two of them sold online.

Moving to historic vehicles, how would I find out which friction rating
of oak is?

Or rubber in bicycle brakes.

On Sun, 14 Jan 2018 23:51:59 -0500,
Clare Snyder wrote:

the PRIMARY quality of a brake material that YOU need to worry
about is "performance"
That "performance" includes how well it stops hot and cold, brake
feel, pad life, and rotor life.

Yes. But.
There's no way to tell that if you have two pads in your hands, and even
less of a way to tell if you're buying two pads online.

Remember, *all* the marketing is complete bull**** (refer back to
Axxis, PBR, and Metal Masters - three differently marketed and priced pads,
all exactly the same - and refer to the fact that there are no laws telling
them that a spec of dust isn't ceramic and that a spec of iron isn't
semimetallic.

The only law that I know of is that they can't call a non-asbestos pad that
if it contains asbestos.

Maybe someone here knows the laws, but that's my sad conclusion so far.

The coefficient of friction only affects ONE of those qualities - and
the gross difference between a good e and a poor g is NEGLIGIBLE .
(Both are essentially an F -)

Yes. You have always been right on that. I don't disagree. I was hoping
beyond hope that there was a way for the consumer to tell pad A from pad B
when they are in the consumer's hands.

But it's not possible. Anyone who *thinks* he can tell, is fooling
himself. So every butt-dyno inspired "review" out there is complete
bull**** (and always was for a huge number of reasons).

Everything is bull****.
That's what's so sad.

The only thing we know, by looking at a pad, is who made it, what its
friction coefficient is, and whether or not some other pad is made by that
company and whether or not it's exactly the same friction material.

That's it. Everything else we "think" we know, is complete marketing
bull****.

AN OEM GUALITY brake part will be CLOSE to what was specified by the
manufacturer - may be marginally better or marginally worse - but they
will be close.

Yes. You have always been right, but ... and this is a big butt!

1) If you get OE pads (from the dealer or pads with the exact same DOT Edge
Code), then you get the handling specified by the manufacturer (assuming
your vehicle is essentially the same, e.g., same size tires, same
suspension setup, etc.)

2) Otherwise, if you get somethign that some marketing guy "says" is "OEM
Quality", then you know almost nothing since you have to "ask" what the
**** "OEM Quality" means to the marketing bull****ter who is telling you
that.

So, if it's actually true that it's OEM Quality, then it's OEM Quality.

But what the **** does OEM Quality mean when we already know that the
second-order effects are almost as great as the first order effects here.

Does OEM Quality mean that the shoe has the same friction coefficient?
(Let's hope so - but it's *easy* to find an FF pad, so, it has to be more,
right?)

Does OEM Quality mean the shoe lasts as long?
Is as dustless?
Makes as much noise?
Has the same pedal force per deceleration value?
Outgasses the same?
Fades the same?

Who the **** knows the answer to that question?

The only Occam's Razor logical answer to that question is that OEM Quality
is bull**** unless you *trust* the guy who says it - and even then - he
doesn't know himself - so you'd have to trust the "scientist" who told him
to say that.

I talk to my jobber and ask what their warranty experience is with
different products. If they have noise complaints, or poor wear, on
one brand/model but not on another, I stay away from the one that has
problems.

Yes. I always defer to your greater experience. But I don't have "my
jobber". Heck, you are "my jobber", in effect.

So I understand that if I ask someone who has tons of experience, like you
do, then I can get closer, but even you can't tell me what the difference
is between the $20 pads and the $157 pads unless I dig up all the relevant
information about them, and even then, if your jobber isn't experienced
with them, then I'm back at starting point zero.

So your access to a jobber is great - but I don't have that access.

Years ago I got and read the Service Station and Garage Management
magazine - which had articles about different products - written by
mechanics, not engineers and salemen, reporting both the Gems and the
Stinkers.

Most people think that if you drop a big ball and a small ball, they'll
land at different times. Most people, I think, trust their feelings more
than they trust measurements.

That's why I don't trust butt dyno reports.

People feel their car goes faster if they put in $5/gallon fuel than if
they put in $2/gallon fuel, even if it doesn't. Their reviews are always
written to placate their own preconceived notions.

The *only* review I will trust is a blind review, where the driver doesn't
know anything about the pads, and where that driver didn't write the review
and didn't get paid for writing the review and who doesn't get
advertisement money either.

And that's almost zero reviews.
All those reviews in Car & Driver and Motortrend are bull****, IMHO.

I realize you're talking a *different* kind of mag, so maybe it's not a rag
like those are, but it's not something I'm going to read unless you know of
a brake comparison that is meaningful.

For example, I hear all the time someone claiming their Cooper tire is
better than my Dunlops or Hancook's, but without the manufacturer's
comprehensive tire test for *all* the tires, we have nothing to go by.

Same here.
Just having one test is useless.
The test has to cover all brake pads we have available to us.

And they just don't.

Look for a certified label

As someone else said, the certified label is the receipt which has a zip
code, which proves that you bought the pads in the USA.

The only reliable conclusion we can make is that any pad legally sold in
the USA is about the same in performance as far as anyone can tell just by
looking at the pad.

Unless a scientific test has been run, they're all the same is the only
conclusion anyone can make, since any other conclusion (that they're
different) has to be based on bull****.

That's just sad.

New vehicles must meet federal performance standards+AJc-a minimum
stopping distance in a variety of situations under a specified pedal
effort. Many consumers assume all aftermarket replacement pads will
perform just as well or better than factory parts, but that's not
necessarily the case.

I don't know that new vehicles must meet stopping distance standards but I
don't doubt you as you've been right all along.

However, any pad sold in the US has to also meet standards, and it seems
that any pad works, based on those standards.

I'm not saying that all pads are exactly alike. I definitely think they're
not. I'm just saying that all the information available to us saying they
are not alike, is based on bull**** that isn't backed up by any science
that is available to us.

As the Ameca engineer told me, the guy submitting the material is the only
guy who knows anything about them.

Nobody else does. And even that guy, the Ameca engineer kept telling me,
doesn't know anything about any other material.

In an effort to improve the customer's comfort level+AJc-and also to avoid
future government regulations+AJc-brake manufacturers can test and verify
their products under two voluntary certification standards. Both are
designed to ensure that replacement brakes are as effective as
original equipment, and consumers should make sure that any pads being
installed on their vehicle are certified.

Exactly. I have never been to a mechanic in my entire life, so I don't
really know what *other* people do, but I would *guess* that most people go
to a brake shop like Midas or America's Tire, or the local indy, and they
expect to get brake pads and shoes.

I doubt they ask much about what they got, but if I took a score of cars to
a score of brake shops, I wouldn't be surprised to get more than a dozen
different brands on the vehicle.

Only at the dealer would I expect a specific brand.

Is that a correct assumption? (I have zero experience with mechanics.)

I'll cover the rest separately.
I do appreciate your advice as you have been right all along.
You just happen to have more resources available to you than I have to me.

On Sun, 14 Jan 2018 18:05:29 -0800 (PST),
wrote:

Sigh. It's just sad.

if they all work ok it's not sad, it's a nonissue

I think you hit the reluctant nail on the head!

The only way this can make sense is if all brake pads work. Period.

Because if people were getting into accidents due to bad brake pads,
someone would step in and stop that (we hope).

Notice even the police report, which is the only scientific study we have,
never said any pad was better or worse - they just required more foot
pounds or fewer foot pounds of pedal force for the same deceleration value.

They never said anything about not being able to decelerate at the desired
deceleration value.

So, I very belatedly am getting the lesson that, in terms of stopping a
typical passenger vehicle, all pads sold are just about the same in terms
of performance.

Another way of saying that is that no matter what the price is, you can't
get a bad pad (nor a good pad). All you get is a pad.

All this assumes that you can't afford to run your own scientific tests,
because the one scientific test we do have, concludes as much anyway in
that there's no way to tell unless you run the test yourself, which you
can't do.

For actual racing, those guys can spend the actual immense time comparing
two different pads, but the consumer is left to realize, as sad as this
conclusion is for me to state, that all consumer-available brake pads are
pretty much exactly the same in terms of stopping ability.

Sigh. It's sad. I didn't want to conclude that. I really didn't. But it is
what the science tells us it is. The rest is just marketing bull**** and
fear mongering from the butt-dynos that think if they paid $157 for a pad,
then it must be better than if they paid $20 for the same pad.

On Sun, 14 Jan 2018 17:52:27 -0800 (PST),
wrote:

There are presumably 2nd order differences in pad performance,
but we've no idea what they are. EE versus FF is not it seems
the relevant criterion as long as the car can apply enough force
to lock wheels with the pads.
Whether all modern cars can do that with EE or not I also have
no idea. FWIW certainly all historic ones can't.

I agree with you that the primary role of friction material is their
friction, but as the AMECA engineer told me, the way they outgas alone can
have an effect that is huge, as you are also noting.

It would be nice to figure out what these second-order effects are, such as
outgassing as mentioned by the AMECA engineer, as the police cruiser test
already eliminated any second-order effects from a difference in vehicles
since they tested the different pads on the exact same vehicle.

So we can tentatively state that you are 100% correct that second-order
effects (outgassing) apparently are as big as first-order effects
(friction).

The AMECA engineer said that all materials heat up differently, which, he
said, also effects the performance of the pads.

So I think we have two potentially high second-order effects which are
(shockingly) almost as important as the first-order effect of friction
coefficient:
1) outgassing (outgasing sp?)
2) heating
3) ?

What other potentially very high (as high as friction) second-order effects
could we have, when we've eliminated the difference in vehicles and driver?

On Mon, 15 Jan 2018 14:19:45 -0000 (UTC), Mad Roger
wrote:

On Sun, 14 Jan 2018 17:52:27 -0800 (PST),
wrote:

There are presumably 2nd order differences in pad performance,
but we've no idea what they are. EE versus FF is not it seems
the relevant criterion as long as the car can apply enough force
to lock wheels with the pads.
Whether all modern cars can do that with EE or not I also have
no idea. FWIW certainly all historic ones can't.

I agree with you that the primary role of friction material is their
friction, but as the AMECA engineer told me, the way they outgas alone can
have an effect that is huge, as you are also noting.

It would be nice to figure out what these second-order effects are, such as
outgassing as mentioned by the AMECA engineer, as the police cruiser test
already eliminated any second-order effects from a difference in vehicles
since they tested the different pads on the exact same vehicle.

So we can tentatively state that you are 100% correct that second-order
effects (outgassing) apparently are as big as first-order effects
(friction).

The AMECA engineer said that all materials heat up differently, which, he
said, also effects the performance of the pads.

So I think we have two potentially high second-order effects which are
(shockingly) almost as important as the first-order effect of friction
coefficient:
1) outgassing (outgasing sp?)
2) heating
3) ?

What other potentially very high (as high as friction) second-order effects
could we have, when we've eliminated the difference in vehicles and driver?



Pad vibration - which has an effect on gas venting, counterd by the
effect of reduced pad contact

May not be a HUGE difference, but it is possibly a factor. Also heat
CONDUCTANCE - metallic pads conduct more heat to the caliper than
ceramice - making the boiling point of the fluid more critical (if
running metallic or semi-metalic pads you want to be sure to be
running DOT4, not DOT3, and you want it freash and dry) One reason
Chrysler was using composite pistons for several years in the early
no-asbestos days (until they found the pistons swelled and stuck - - -
)

On Sunday, January 14, 2018 at 11:52:04 PM UTC-5, Clare Snyder wrote:




New vehicles must meet federal performance standards€”a minimum
stopping distance in a variety of situations under a specified pedal
effort. Many consumers assume all aftermarket replacement pads will
perform just as well or better than factory parts, but that's not
necessarily the case.

This whole thing seems a bit silly to me. It's a test for police
cars. I would expect that all cars can lock the wheels with a
power assisted force that's well within the range that a typical
driver can apply. That's one of the reasons we went to anti-lock
brakes, right? Because once it's locked, you need to release force
to keep it moving to keep control. So, why police would be so worried
about how much force it takes on the pedal, IDK. ARe they such wusses
that they can't apply reasonable force that would lock the wheels
in panic situations? Those force numbers required are all within what
any cop that's fit for duty can apply. So, what's the point?
I agree with Clare, there are plenty of other issues here that are
more important than the friction. IMO, unless it's some unusual
situation, this friction thing is mostly a red herring in selecting
brake pads.

On Monday, January 15, 2018 at 9:19:48 AM UTC-5, Mad Roger wrote:
On Sun, 14 Jan 2018 18:05:29 -0800 (PST),
wrote:

Sigh. It's just sad.

if they all work ok it's not sad, it's a nonissue

I think you hit the reluctant nail on the head!

The only way this can make sense is if all brake pads work. Period.

Because if people were getting into accidents due to bad brake pads,
someone would step in and stop that (we hope).

Notice even the police report, which is the only scientific study we have,
never said any pad was better or worse - they just required more foot
pounds or fewer foot pounds of pedal force for the same deceleration value.

Bingo. Cops are supposed to be reasonably physically fit. We went
to anti-lock brakes because the regular drivers were locking the breaks.
I've never had a car with any brake pads where I could not very easily
with limited force, lock the brakes. So, why the obsession with the
coefficient of friction? For the typical driver, how much brake dust
they put out is more of an issue. I can see the coefficient of friction
affecting how they feel, whether you need to put X force that;s within
your ability to lock them, or X plus some force that's still well within
your ability to lock them, but that's all.





They never said anything about not being able to decelerate at the desired
deceleration value.

Bingo again.



So, I very belatedly am getting the lesson that, in terms of stopping a
typical passenger vehicle, all pads sold are just about the same in terms
of performance.

For a typical drive, I agree. If you're talking about a race track,
someone with big loads going down hill, etc, then other factors, like
fade performance could make a difference.



Another way of saying that is that no matter what the price is, you can't
get a bad pad (nor a good pad). All you get is a pad.

That depends on your criteria. If you hate dust for example, there are
pads that put out a lot of dust and pads that don't put out very much.
There are pads that last longer than others.




All this assumes that you can't afford to run your own scientific tests,
because the one scientific test we do have, concludes as much anyway in
that there's no way to tell unless you run the test yourself, which you
can't do.

For actual racing, those guys can spend the actual immense time comparing
two different pads, but the consumer is left to realize, as sad as this
conclusion is for me to state, that all consumer-available brake pads are
pretty much exactly the same in terms of stopping ability.

Sigh. It's sad. I didn't want to conclude that. I really didn't. But it is
what the science tells us it is. The rest is just marketing bull**** and
fear mongering from the butt-dynos that think if they paid $157 for a pad,
then it must be better than if they paid $20 for the same pad.

And that comes as a surprise to you? I see people online,
cheerfully running down to the stealership, to buy the dealers
oil at $9 a quart, or their antifreeze, or a part, etc when there are
equivalent products available on the market for a fraction of
the price. And it doesn't just apply to cars. Monster and similar
audio cables that are oxygen free, or pure, or whatever been an
excellent example.

On Mon, 15 Jan 2018 14:19:42 -0000 (UTC), Mad Roger
wrote:

On Sun, 14 Jan 2018 23:51:59 -0500,
Clare Snyder wrote:

the PRIMARY quality of a brake material that YOU need to worry
about is "performance"
That "performance" includes how well it stops hot and cold, brake
feel, pad life, and rotor life.

Yes. But.
There's no way to tell that if you have two pads in your hands, and even
less of a way to tell if you're buying two pads online.

Remember, *all* the marketing is complete bull**** (refer back to
Axxis, PBR, and Metal Masters - three differently marketed and priced pads,
all exactly the same - and refer to the fact that there are no laws telling
them that a spec of dust isn't ceramic and that a spec of iron isn't
semimetallic.

The only law that I know of is that they can't call a non-asbestos pad that
if it contains asbestos.

Maybe someone here knows the laws, but that's my sad conclusion so far.

The coefficient of friction only affects ONE of those qualities - and
the gross difference between a good e and a poor g is NEGLIGIBLE .
(Both are essentially an F -)

Yes. You have always been right on that. I don't disagree. I was hoping
beyond hope that there was a way for the consumer to tell pad A from pad B
when they are in the consumer's hands.


OK - we've gotten off the subject of brake SHOES - wherer there is a
lot less difference in materials and construction - but with PADS
there are several things you can consider that are NOT "marketing
bull****"

Metallic pads are more aggressive than ceramics and organics (and they
are harsher on rotors and noisier)
Ceramics last longer and dust less - and stop better than organics,
but are not as effective when cold as metallics.
Ceramics can have small amounts of iron, steel, copper, or brass in
them -as can "organics The tree-huggers in Cali are trying to outlaw
copper bwcause it kills alge etc in runoff water fromthe roads -
leaving us with the more agressive ferrous materials.

You can tell if a ceramic or semi-metallic pad is using ferrous
materials with a magnet.

For rear brake SHOES a good organic material is usually your best bet
- they do not do a lot of the stopping, so generally outlast front
pads by a LARGE margine and unless towing, heavy loads, or extreme
duty they seldom get hot enough to fade much (compared to front brakes
- where droms significantly outperform discs in initial stopping
power, but quickly loose efficiency due to heat.

The MAJOR companies - I'm not talking your second and third tier
"boutique" rmarketers likw those favourite brands of yours - do
SIGNIFICANT reasearch and engineering, often develloping specific
friction materials (and combinations) for different vehicles. The
Wagner thermoquiet formulation on your Ford may be significantly
different than on your Dodge or GM, or Toyota.

You decide which characteristics are impoetant to you - extreme high
speed performance at the expense of life and quiet and dusting, or
silence, long rotor life, and low cost at the expense of high speed
performance and pad life, or good all-round performance, pad life, and
rotor life at a significantly higher cost to decide if you want
semi-metallic, organic, or ceramic pads, then you go to a trusted
reseller of a major brand - wagner, TRW, Akebono, Brakebond, Mintex
rtc and buy their premium (highest quality) set of whichever
technology meets your desires.

I say the "premium" set meaning the one that comes with all the
required clips, shims, pins, etc to do a proper install without having
to source other parts elsewhere or re-use sub-optimal used parts.


But it's not possible. Anyone who *thinks* he can tell, is fooling
himself. So every butt-dyno inspired "review" out there is complete
bull**** (and always was for a huge number of reasons).

Everything is bull****.
That's what's so sad.

Engineering isn't bull****. As an "engineer" you should appreciate
that anless you got your degree in a box of crackerjacks.

The SCIENCE is there. (mixed with a bit of black magic - as all
"science" is)

When you buy from Rock Auto, you are USUALLY buying prime product that
came off someone's shelf when they went out of business, or warehouse
overstock, or "open box" product, or product with damaged packaging
due to fading from being on a shelf too long, moisture damage, smoke
damage, etc. When you buy "brand name" from them, you are generally
getting top quality genuine pruduct at pennies on the dollar.

That's why their prices are generally so good (if, unlike here in
Canada, the shipping costs don't totally wipe out the savings in so
many cases)

Taking into account the exchange rate and shipping, I can GENERALLY
buy , say, Wagner, from Napa or Parts Source for VERY close to the
same price as I can buy from Rock.

The only thing we know, by looking at a pad, is who made it, what its
friction coefficient is, and whether or not some other pad is made by that
company and whether or not it's exactly the same friction material.

That's it. Everything else we "think" we know, is complete marketing
bull****.


No, in your case it is shear paranoia, over a base layer of
ignorance.
AN OEM GUALITY brake part will be CLOSE to what was specified by the
manufacturer - may be marginally better or marginally worse - but they
will be close.

Yes. You have always been right, but ... and this is a big butt!

1) If you get OE pads (from the dealer or pads with the exact same DOT Edge
Code), then you get the handling specified by the manufacturer (assuming
your vehicle is essentially the same, e.g., same size tires, same
suspension setup, etc.)

2) Otherwise, if you get somethign that some marketing guy "says" is "OEM
Quality", then you know almost nothing since you have to "ask" what the
**** "OEM Quality" means to the marketing bull****ter who is telling you
that.


Fiorget your paranoia about "marketting bull****" It is BULL****.
Don't get your technical information from know-nothing boy-racers
blogging on the internet, or reviews opn Amazon,or advertizing in
enthusiast magazines. Get your info from "trade magazines" and major
suppliers to the automotive TRADE.

Buy STEAK, not Sizzle. Forget your boutique brand crap. If your
favourite brands were as good as you seem to think they are, they
would have displaced TRW, WAGNER, Akebono, and the other major OEM
SUPPLIERS as the major aftermarket suppliers.

WHo do you think engineers and manufactures the OEM brake material for
Ford, GM, Toyota,Chrysler, etc?

They do NOT design and manufacture the stuff themselves. They have
that done by the likes of Wagner, TRW, Akebone, American Brakebond,
etc. These are the major suppliers to BOTH the OEM and the aftermarket
and OEM REplacement .

For good reason. They have the engineering, and they have the
"critical mass" to be able to produce quality at a reasonable price.

Don't be such a stiubborn paranoid "engineer". YOU will NEVER
understand EVERYTHING about your OWN field of expertise, muchless a
field totally outside your reralm.

Concentrate on becoming the BEST ELECTRICAL ENGINEER you can be and
let the automotive engineers do their job., Along with the materials
engineers, physicists, chemists, and wizards their potions and
perscriptions are working pretty good.

When you start to build specialized race vehicles or highly modified
special purpose vehicles, you go to the engineers with a blank
checquebook and have them come up with the specialized solution you
require - or you go to an "application engineer" and have him pick the
best off-the-shelf solution for your application - at a significantly
lower price point and a much better chance of initial success.
So, if it's actually true that it's OEM Quality, then it's OEM Quality.

But what the **** does OEM Quality mean when we already know that the
second-order effects are almost as great as the first order effects here.

OEM means BASICALLY THE SAME DESIGN as OEM - so the second and third
order effects are taken intoaccount the same asthe OEM. This can NOT
be done by a "boutique" marketing company that buys their product out
of the discard bucket of some chinese sweatshop, or off the back
loading dock.

ONE of your "favorite brands" - pehaps MetalMaster -whichever one is
charging the highest price, most likely paid some shop in China to
produce their product afterr having paid some qualified enginners to
come up with the specs and formulation - then the unscrupulous
"*******s" in China unloaded a few containerloads out the back door to
some chinese marketing company who sold them to the other 2
manufacturers. - and quite possibly cheapened the product - possibly
even to the initial purchacer - by substituting inferior raw
materials, or cuttin corners on production - to sell it at a better
price to the other companies - without ever changing the stamp on the
material.

I've had dealings with the scoundrels, where my company paid for the
design and tooling for a product, only to have it on the cover of
"asian sources Computer" magazine for half what we were paying for it
before we even got our first containerload.

You deal with Chinese Industry at your peril. If you have FULL CONTROL
you MAY come out unscathed (Full control is a mirage)

Your 3 products MAY be the same. They MAY all be legitimate. They MAY
actually meet the specs stamped on them - but certainly do NOT bet
your life on it.

When I buy Wagner or Akebono aftermarket OEM Replacement parts, etc
from a supplier like NAPA i KNOW what I am getting.

Does OEM Quality mean that the shoe has the same friction coefficient?
(Let's hope so - but it's *easy* to find an FF pad, so, it has to be more,
right?)

Does OEM Quality mean the shoe lasts as long?

OEM Quality means it meets the specifications of the OEM product - in
all the major areas including stopping power/performance, feel, and
life.
Is as dustless?
Makes as much noise?
Has the same pedal force per deceleration value?
Outgasses the same?
Fades the same?

Who the **** knows the answer to that question?

Certainly you don't, and never will if you don't listen and get
treetment for your paranoia.

The only Occam's Razor logical answer to that question is that OEM Quality
is bull**** unless you *trust* the guy who says it - and even then - he
doesn't know himself - so you'd have to trust the "scientist" who told him
to say that.

Get back on your medications - and if you have never been medicated,
see a professional for dianosis and a perscription as soon as possible

I talk to my jobber and ask what their warranty experience is with
different products. If they have noise complaints, or poor wear, on
one brand/model but not on another, I stay away from the one that has
problems.

Yes. I always defer to your greater experience. But I don't have "my
jobber". Heck, you are "my jobber", in effect.

I have the advantage of being a legitimate tradesman with links to
the automotive oem replacement and afterrmarket locally, and am known
(and respected) by many of them even though I have been actively out
of the trade for over 2 decades - they don't "bull****" me. If they
try, they find out pretty quickly that it doesn't work.

They can usuallyspot a "poser" pretty quickly.

So I understand that if I ask someone who has tons of experience, like you
do, then I can get closer, but even you can't tell me what the difference
is between the $20 pads and the $157 pads unless I dig up all the relevant
information about them, and even then, if your jobber isn't experienced
with them, then I'm back at starting point zero.

I can tell you your $20 pads are NOT ceramic - almost 100% guaranteed
- and I can tell you the $157 pads arer NOT simple organics - almost
100% guarantee. I can also tell you if you are buying "boutique"
brands you are likely overpaying for whatever it is you are buying.

If I have them in my hand I can give you a pretty good guess as to
how they will stand up, and what affect they will have on your rotors.

You do not have this knowlege, and are very unlikely to ever gain
that knowlege because it comes with experience, along with training
and research in a field in which you have not got the training, and
your level of paranoia precludes you EVER absorbing the knowlege
offered to you.

So your access to a jobber is great - but I don't have that access.
You have access to trade supplies like NAPA. Sadly they will sell to
anyone who darkens their door.

Years ago I got and read the Service Station and Garage Management
magazine - which had articles about different products - written by
mechanics, not engineers and salemen, reporting both the Gems and the
Stinkers.

Most people think that if you drop a big ball and a small ball, they'll
land at different times. Most people, I think, trust their feelings more
than they trust measurements.

And if you are any kind of an engineer you KNOW that you have
oversimplified that last statement
A 10 lb beach ball and a 10lb bowling ball WILL fall at a different
speed in free air. Youdidn't take into account the difference in wind
resistance due to size.

Not only that, a pingpong ball and a baloon will also fall at
different speeds. - and if the balloon is full of hot air or helium it
won't fall at all.

You simplify things way too much on one hand, and complicate them way
to much onthe other.

I'd hate to have you design an electrical control system for me if
your grasp of electrical engineering is as poor as your grasp of
physice and aerodynamics - - -


"There are 10 kinds of people in the world - those who understand
binary logic and those who don't"

That's why I don't trust butt dyno reports.

People feel their car goes faster if they put in $5/gallon fuel than if
they put in $2/gallon fuel, even if it doesn't. Their reviews are always
written to placate their own preconceived notions.

If you spend megabucks on something, and stake your reputation on
being right, then of course everthing you buy MUST work.

I had a brother inlaw who died of cancer because he KNEW the product
he had been selling and using cured cancer - so there was NO WAY his
cancer had come back If he admitted he had cancer again, he had lied
to everyone he peddled the stuff to and his life had been a lie - so
he didn't have cancer - untill it killed him.

The *only* review I will trust is a blind review, where the driver doesn't
know anything about the pads, and where that driver didn't write the review
and didn't get paid for writing the review and who doesn't get
advertisement money either.

Like the double blind study done by Nokian with the automotive press
on their Hakkapelitta snow tires.
Nobody knew which cars had what tires on them during the tests - but
the experienced drivers could tell.

And that's almost zero reviews.
All those reviews in Car & Driver and Motortrend are bull****, IMHO.

I realize you're talking a *different* kind of mag, so maybe it's not a rag
like those are, but it's not something I'm going to read unless you know of
a brake comparison that is meaningful.

For example, I hear all the time someone claiming their Cooper tire is
better than my Dunlops or Hancook's, but without the manufacturer's
comprehensive tire test for *all* the tires, we have nothing to go by.

Well, I KNOW that some coopers are better than some Duinlops - and
also that some dunlops are better than some Coopers, and a few years
back just about ANYTHING was better than a Hankook. I also know that
Hankook builds and sells some pretty decent tires today. (and like
most manufacturers - some total CRAP.

I also know that many "northamerican brand" tires are now made in
China or Korea, or Thailand or VietNam.

Same here.
Just having one test is useless.
The test has to cover all brake pads we have available to us.

And they just don't.

Look for a certified label

As someone else said, the certified label is the receipt which has a zip
code, which proves that you bought the pads in the USA.

BUll****. Read the article I posted for you. It is an international
certification program - independent of the manufacturer

The only reliable conclusion we can make is that any pad legally sold in
the USA is about the same in performance as far as anyone can tell just by
looking at the pad.

Unless a scientific test has been run, they're all the same is the only
conclusion anyone can make, since any other conclusion (that they're
different) has to be based on bull****.

That's just sad.

What is REALLY sad is you are so mired in Bovine Excement and
paranoia that you can't see the forest for the trees.

New vehicles must meet federal performance standards+AJc-a minimum
stopping distance in a variety of situations under a specified pedal
effort. Many consumers assume all aftermarket replacement pads will
perform just as well or better than factory parts, but that's not
necessarily the case.

If you buy QUALITY replacement parts, they will meet or excede those
specs. If you buy boutique crap online you have no assurances at all.

I don't know that new vehicles must meet stopping distance standards but I
don't doubt you as you've been right all along.

However, any pad sold in the US has to also meet standards, and it seems
that any pad works, based on those standards.

There are standards, and there are standards. Any pad legitimately
sold in North America wilkl stop your unloaded $ Runner at legal
speeds under normal conditions. - For a while.

I'm not saying that all pads are exactly alike. I definitely think they're
not. I'm just saying that all the information available to us saying they
are not alike, is based on bull**** that isn't backed up by any science
that is available to us.

Your paranoia and ignorance is showing - BIG TIME.

If I put Wagner Thermoquiet ceramic pads on the front of my vehicle,
and wagner or monroe premium shoes on the rear, with good rotors and
pads (no grooves or glazing) and I properly break them in, I KNOW I
will be stopping well for the next couple of years or 10-20000km with
no issues IF I service the front calipers regularly to be sure the
sliders don't stick - and that's here in the "rust belt" of Central
Ontario.

I also know, from experience, that if I pay 3 times as much for EBC
greenstuff pads from some performace shop for my "Mondeo" as what I
pay for OEM wagners, they don't last any longer or stop any better
than if I put on Wagner Semi Metallics. Been there - done that -
threw away the awful "t" shirt ---

As the Ameca engineer told me, the guy submitting the material is the only
guy who knows anything about them.

Nobody else does. And even that guy, the Ameca engineer kept telling me,
doesn't know anything about any other material.

ANd the guy who submits it may not know squat about it either other
than where he had it made and by who.

In an effort to improve the customer's comfort level+AJc-and also to avoid
future government regulations+AJc-brake manufacturers can test and verify
their products under two voluntary certification standards. Both are
designed to ensure that replacement brakes are as effective as
original equipment, and consumers should make sure that any pads being
installed on their vehicle are certified.

Exactly. I have never been to a mechanic in my entire life, so I don't
really know what *other* people do, but I would *guess* that most people go
to a brake shop like Midas or America's Tire, or the local indy, and they
expect to get brake pads and shoes.

Perhaps three of the WORST places to go - and your " I have never
been to a mechanic in my entire life," speeks volumes - if nothing
else - about your combination of paranoia and ignorance.

I doubt they ask much about what they got, but if I took a score of cars to
a score of brake shops, I wouldn't be surprised to get more than a dozen
different brands on the vehicle.

ANd if you took them to those brake shops, you will have paid more
than necessary and gotten less than you paiud for unless you knewa lot
more than you do.

Only at the dealer would I expect a specific brand.

Is that a correct assumption? (I have zero experience with mechanics.)

Totally wrong. Go to a Napa Autopro garage and you will get product
sold by NAPA - either their own brand or a national brand - either
economy or premium - depending on what you are willing to pay.

The fact you have "no experience with mechanics" and yet you are so
paranoid speeks volumes. A young graduate engineer with no experience
and an inflated opinion of himself and his knowlege in a field for
which he has NO TRAINING. Don't know about where you are, but I had5
years of training before I could call myself a mechanic.
As a teacher of automechanics I had to make sure my students had a
good grasp of elementary physics (levers, ratios,mechanical
advantage,friction and lubrication) and the related maths, as well as
electricity and electronics, plumbing, machining,some thermodynamics,
as well as hoiw to properly select and use the proper tools for a job
and to work safely. And on top of that, I had to teach them about
"auto mechanics".

After becoming a registered. "licenced" mechanic I took courses put on
by the trade suppliers and the oil companies (when I worked at service
stations) and the manufacturers (when I worked for a dealership) to
keep up to the "state of the art" in products, tools, and diagnosis
methods, (troubleshooting) among other things.

I'll cover the rest separately.
I do appreciate your advice as you have been right all along.
You just happen to have more resources available to you than I have to me.


You have all the "resources" available to you that I have, except for
experience and intuation (born from that experience, as well as
specialized training). Nothing I have quoted or provided for you came
from anywhere that is not readilly available to you - at your keyboard
- if you have half a clue where to look and how to find it.


Along with close to 3 decades of working in the automotive trade I
have close to another 3 decades working in information technology
The secret is knowing fly**** from pepper.

Some of that comes from experience. Some of it comes from "inate
intelligence" and "aptitude" which some are born with, and some are
totally devoid of - no matter HOW much education they get.

On Mon, 15 Jan 2018 14:19:44 -0000 (UTC), Mad Roger
wrote:

On Sun, 14 Jan 2018 18:05:29 -0800 (PST),
wrote:

Sigh. It's just sad.

if they all work ok it's not sad, it's a nonissue

I think you hit the reluctant nail on the head!

The only way this can make sense is if all brake pads work. Period.

Because if people were getting into accidents due to bad brake pads,
someone would step in and stop that (we hope).

Notice even the police report, which is the only scientific study we have,
never said any pad was better or worse - they just required more foot
pounds or fewer foot pounds of pedal force for the same deceleration value.

They never said anything about not being able to decelerate at the desired
deceleration value.

The tests were limited - addressing the use a cruiser puts the brakes
to. If you know how to read the information, it tells you a LOT about
the brakes - but you are correct - there is no "best" brake material -
it depends onthe use they are being put to, and what YOU want from
them. There may well , however, be " WORST" brakes.

If brakes require higher pedal pressure to stop in a longer distance
(and decellerate at a lower rate) both when cold and at normal
temperature, and fade significantly on the second and third
application - they are pretty crappy brakes.

If they require low pedal pressure to decellerate quickly to a stop in
a short distance when both cold and at normaltemperatures, AND do not
fade appreciably on the second and third (panic) stop - they are
pretty darn good brakes - anlness they squeal like a stuck pig, only
last for a month of driving, and/or destroy brake rotors - and/or coat
the wheels with nasty corrosive brake dust - - -

So, I very belatedly am getting the lesson that, in terms of stopping a
typical passenger vehicle, all pads sold are just about the same in terms
of performance.

No, not at all - you are TOTALLY missing the point.
The different brake PAD materials are mission specific.
A ceramic pad will outstop a economy organic pad when hot - hands
down. Every time.
A metallic pad will usually stop better after several panic stops, or
when towing a heavy trailer down a longhill - than either the organic
or the ceramic. Both the semi metallic and the organic will stop
better on a cold stop than a ceramic.

Another way of saying that is that no matter what the price is, you can't
get a bad pad (nor a good pad). All you get is a pad.

No. a $85 Thermoquiet Ceramic will stop better than a $20 no-name
organic pad - and you can be pretty well assured you will not get a
$20 ceramic pad unless Rock Auto has something on clearout.

Price is not a sure predictor of quality - but can be a pretty darn
good indicator.

Also, a high iron semi metallic WILL wear out your rotors faster than
either the organic or the ceramic unless the organic causes the rotor
to blister because of uneven pad material transfer, and abuse.

What you TOTALLY do NOT understand is how disc brakes, in particular,
work - and how the co-efficient of friction changes.

When you "bed in" pads, you are burnishiung a thin coating of pad
material into the finish of the rotor.. The stopping power of the
brake depends on the co-efficient of friction between this burnished
in friction material and the pad - not between the pad and bare metal.
How this coating is applied, and maintained, dictated the braking
charachteristics of a disc brake as much as anything. If you stop hard
and fast and keep your foot onthe pedal at a stop untill the brake
cooles,there will be a heavier deposit on the rotor at that point -
UNLESS the padmaterial deposited on the rotor does not adhere properly
and it pulls away with the pad. Either way you will end up with uneven
braking - either a "thump" or a "skip" on the next brake application.

A "quality": pad will transfer evenly and bond reliably to the rotor
during the perscribed "bed-in" and will not cause uneven transfer
under "normal" driving conditions. It will also not cause or promote
corrosion between that pad mnaterial and the rotor steel (which causes
"scabbies" and pitted rotors (often mistaken for the less common, but
sometimes "real" "warped rotor".

Inferior brake friction material performs more poorly in these ways
than premium materials.

A worn, glazed, or grooved rotor will not "bed in" reliably because
the surface will heat and cool unevenly - with uneven pressure across
the brake surface -

So brake friction material quality AND the installation affect brake
performance.

Also, the brake mounting hardware - the shims and springs either
provided with the new pads, purchased separately, or salvaged from the
prior installation (whether OEM or aftermarket or totally missing)
alsohave effects on the performance (and life) of the brakes. Heat
transfer, Vibration, and freedon to move in the caliper, are all
effected by the quality and presence of the proper mounting hardware -
which is designed/modified by the pad manufacturer to matvch the
characteristics and requirements of their particular pad and friction
material - which is why "premium"brake kits are supplied with the
proper hardware to install the brakes for their best performance.

All this assumes that you can't afford to run your own scientific tests,
because the one scientific test we do have, concludes as much anyway in
that there's no way to tell unless you run the test yourself, which you
can't do.


More paranoid bull****.


For actual racing, those guys can spend the actual immense time comparing
two different pads, but the consumer is left to realize, as sad as this
conclusion is for me to state, that all consumer-available brake pads are
pretty much exactly the same in terms of stopping ability.


Total bull****. The friction rating doesn't tell you much, but the
difference in required pedal pressure, and the difference in stopping
distance - notto mention the difference in pad temperature between the
best and worst in the test is VERY significant.
What is NOT significant is the predictabiklity of the results based
on the frictionrating of the pads under test. (almost totally useless)

Sigh. It's sad. I didn't want to conclude that. I really didn't. But it is
what the science tells us it is. The rest is just marketing bull**** and
fear mongering from the butt-dynos that think if they paid $157 for a pad,
then it must be better than if they paid $20 for the same pad.


WRONG.
And do your friend a favour and send them to a REAL mechanic to have
their brake work done. I fear you are DANGEROUS.

On Mon, 15 Jan 2018 14:19:40 -0000 (UTC), Mad Roger
wrote:

On Sun, 14 Jan 2018 17:58:04 -0800 (PST),
wrote:

That's retail.

That's why I say those who say "you get what you pay for" are misguided
because a $157 pad "might" be just as good or bad as a $20 pad, where I can
prove this statement for the $300 20W Panasonic speakers in a Toyota since
I know the specs on the $50 speakers at Crutchfields.

You still have not learned ANYTHING?????

The specs on speakers are known to be some of the best fiction ever
written, followed only by the specs on consumer stereo equipment.

Even at Crutchfields, you can get a good $50 speaker or a less-good $50
speaker, and the price is exactly the same.

So if someone tells me "you get what you pay for", they'll get the same
rant from me that everyone loves to pick products off a number line, but
the real number line is a bunch of specs, and not a simple price.


You "only" get what you pay for - and then only if you are both lucky
and astute. You SELDOM get more than what you pay for

You can take THAT to the bank.

That's retail for you!

And really the difference is greater, I once bought a set of 4 brake
shoes for +AKM-1, that's under $2. They performed without any issue. Why?

Because someone was unloading something they didn't need, at a price
to get it off their shelves - and your requirements were not severe
enough to require anything better.

I've also been "lucky" enough to pick up some real "bargoons" by
being at the right place at the right time. I often buy what no-one
wants any more - nobody inOntario wanted a 1972 Pontiac Firenza in
1974 or 1975 - so I gor an almost pristine Vauxhaul Viva HC Magnum
coupe for $75 - and it served me well for a number of years before I
sold it to a friend of my wife, who needed a car and had no money for
something "good" - and she drove it another 7 years untill it required
a part that was not readily available or available at a decent cost .

I got "more than my money's worth" - I got "more than I paid for".

The same with my current pickup truck which I bought for $1500 because
nobody wanted a meticulously maintained 16 year old ford Ranger with
over 300,000km on it. It's been virtually trouble free for 6 years -
I've spent about $1500 on repairs over more than 50,000km, and all
indications areI'll get a few more years out of it. I got more than
my money's worth.

In both cases It was because I new the "value" of what I was buying
better than both the seller and other potential buyers.

You are FAR more likely to get less than you paid for - particularly
when buying any commodity new at retail - where you are SIGNIFICANTLY
less likely to get more than you pay for.

Price is not an accurate predictor of quality, but with a few other
often obvious clues, it is a pretty reliable indicator.

I think price is not an indication of anything other than what the
marketing can make people pay. It's certainly not an indication of quality.

It is, as I have stated, an indicator, but not a predictor or
guarantee of quality.

No-one here wants to buy brake parts from scrapyards, even though
they're the same parts you get in the shops.

No they are not - and in MANY places it is illegal to sell used brake
parts and used exhaust/emission parts.

I'm not sure what you mean by "scrapyards". To me, that means a junk yard,
which contains dead cars. I wouldn't buy brakes off a dead car for a
billion reasons which are obvious so I shouldn't need to state it.

Sometimes a car ends up in a scrapyard with lots of brand new parts
on it. The owner puts $3000 into making it safe to drive - new brakes,
suspension,and tires - the either has it hit, or blows a motor or
transmission, and decides not to keep it and repair it - or they spend
all kinds of money fixing it up - making it into their ":boy racer's
wet dream" and then cannot get it to pass smog - and it ends up in the
scrapyard with LOTS of good and/or expensive parts on it.

That said - as a matter of principal - unless no other adequate
source of brake parts was available, I'd be looking elsewhere - first.
Have I used "used" brake parts in the past??
Yes. I put a complete used rear axle from a '63 Belvedere into my '53
Coronet - brakes and all - as an upgrade when the originals failed and
OEM parts were not readilly available, and the old design was less
than optimal.
ANd I put used parts on my '49 VW in Livingstone Zambia. Where was I
going to get new parts??????? On a Sunday afternoon half way between
Choima and Macha - (look it up on Google Earth - and keep in mind
this was 44 years ago - - - - .

What's the difference between my concept of a junkyard (which contains
entire cars that were thrown away) and your scrapyard?

Are you talking about *used* brake pads or *new* brake pads?

if both do the job ok, $20 is the intelligent buying decision.

Not necessarilly.

There is no other logical conclusion to be made, given the information we
have. Price is NOT the determinant of a good or bad brake pad.

Perhaps not of a good one, but quite often of an inferior one

The sad thing is that there is no determinant we can make that will hold
true other than there is no difference practically that you can do anything
about.

again, bushels of bovine excrement.

I'm NOT saying they are all the same. I'm saying we consumers can't tell by
having two of them in our hand or having two of them sold online.

And why do you, like so many "millenials" (I'm aking an assumption
here from significant evidence) INSIST on buying everything
on-line????

Moving to historic vehicles, how would I find out which friction rating
of oak is?

Obviously not sufficientfor a 3 ton vehicle going 100MPH - and
definitely not as good after a long downhill stop - -- but likely, at
low speeds - al ot better than you suspect!!!

Or rubber in bicycle brakes.

There is SIGNIFICANT difference between different compounds of
"rubber" pads for rim brakes - includingin their stopping power and
their destructive effect on rims - some better for chromed rims, and
others for Alloy rims - some working better for side-pull, and others
for center pull (different amounts of pressure available)

On Mon, 15 Jan 2018 15:34:13 -0500, Clare Snyder
wrote:

see http://journals.sagepub.com/doi/full...87814016647300 for an extensive explanation of friction materials from an engineering pwerspective - the english isn't particularly good but LOTS of information

On Mon, 15 Jan 2018 15:34:13 -0500, Clare Snyder
wrote:

More of "all you ever wanted to know about friction materials" but
were afraid to ask - - -

http://www.sae.org/events/bce/tutorial-bahadur.pdf

and

http://www.tomorrowstechnician.com/u...-formulations/

and

http://www.mdpi.com/2075-4442/4/1/5/htm

and

http://www.marathonbrake.com/product...pplication/ub/

and

https://info.ornl.gov/sites/publicat...s/Pub57043.pdf

and

a whole lot more!!!!!!!!!!!

On Mon, 15 Jan 2018 16:09:47 -0500, Clare Snyder
wrote:

On Mon, 15 Jan 2018 15:34:13 -0500, Clare Snyder
wrote:

see http://journals.sagepub.com/doi/full...87814016647300 for an extensive explanation of friction materials from an engineering pwerspective - the english isn't particularly good but LOTS of information


And here is some more real good information on brake pad materials -
on a lower level - for the non-engineers out there.