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Mad Roger Mad Roger is offline
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Default Need help INTERPRETING these test results police cruiser SAE J866a Chase Test

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

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

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.