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Clare Snyder Clare Snyder is offline
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Default Need help INTERPRETING these test results police cruiser SAE J866a Chase Test

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

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

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

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"