View Single Post
  #42   Report Post  
Posted to,,
Mad Roger Mad Roger is offline
external usenet poster
Posts: 192
Default Need help INTERPRETING these test results police cruiser SAE J866a Chase Test

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

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

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

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,

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

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

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.