Need help INTERPRETING these test results police cruiser SAE J866a Chase Test

On Tue, 16 Jan 2018 08:52:07 -0800 (PST), snipped-for-privacy@gmail.com wrote:


I agree with your logical thought process in that the only scientific summary that makes logical sense is that all pads work just fine in passenger vehicles, with the main difference being the foot pounds of torque applied to the brake pedal to obtain the desired deceleration rate.
Hence, any pad is fine, EE or FF or GG, for stopping the vehicle.

I go though a set of front pads once every couple of years, never more than two years on my own vehicle, but on this vehicle, it took 20 years to go through one set of rear shoes.

The problem isn't the scrapyard per se. The problem is getting the *right* pads at the scrapyard. That can't be easy (see my other post on how that's done).

What does that even mean?

I don't at all disagree with your apropos logic that every time you buy a used car you get used pads, but, you can assume (logically) that the pads fit.
I've been to junk yards where there literally are junked cars piled four and five cars high outdoors, where you walk the yard looking for the fender or mirror that you want.
To look for brake pads would be an order of magnitude harder because you can't see the brake pad until you find a similar vehicle make model and year, you climb up to the top car, you remove the wheels, you pull the rusty drums or calipers off, and then, only then, do you get any chance to see the condition of the brake pads and shoes.
Or, if the scrapyard does all that for you, and has placed a ton of brake shoes on the shelves, you can pick among them for the right size and shape, but that process comes with the problem that you have to have a comparison pad and shoe in your hands, which means your car is up on blocks and you're borrowing someone else's car.
If you can read the AMECA edge code, you have a chance at getting the right shoe or pad, but it sure does seem like a lot of effort when an FF pad or shoe is about $20 a set of four at Rock Auto.
Did I surmise the scrap yard process incorrectly? If so, how would you correct that process of *selecting* the right pads?
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On Mon, 15 Jan 2018 09:54:26 -0800 (PST), trader_4 wrote:

Somewhere I read that ABS doesn't stop you in the shortest distance - it just stops you with the most control. Dunno if that's true as that's not what I was aiming for here.

It's not so much an obsession with any one spec but the desire to be able to intelligently compare two brake shoes that are in one's hand or on the web.
It should be clear by now that I don't trust salesmen or marketing, so I'm pretty much stuck to trusting whatever specs we have.
And we *know* that the AMECA Edge Code is one spec that must, by law, be printed on every shoe.

I agree that there are other important criteria of a second-order nature other than how well a shoe stops.
But just stating them doesn't help.
We have to be able to tell how much shoe A dusts compared to shoe B when we go to the parts store or on the web to buy them.
How do YOU tell if shoe A dusts more or less than shoe B for example?

It doesn't even seem to do that, since as Clare noted, EE and FF brakes had pedal forces to maintain a given deceleration that were 100% different and it didn't matter whether they were EE or FF. It was dependent on the pad.
So, we're really stuck with nothing.
As you noted, *lots* of things are important, but that's meaningless if we can't tell, with the shoes in our hand or on the web, which ones are better than the others.
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On 17/01/2018 7:59 AM, Mad Roger wrote:

You read somewhere? If you understand how ABS systems operate you would *inherently know* the answer, not just from *reading it somewhere*.
The fact that you *don't know if the answer you read was true* proves that you are starting from a very low knowledge base and should stay away from brakes, steering, suspension, even cars in general, until you rectify this *knowledge deficit*.
--

Xeno

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wrote:

"antilock brakes just guarantee you will hit whatever you hit SQUARE ON!!!"
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On 17/01/2018 4:07 PM, Clare Snyder wrote:

LOL, they will indeed!
--

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Clare Snyder posted for all of us...

Exactly! When the slickback chevys first came out with ABS the cops were burning up pads and crashing early and often. They had to be *retrained* to keep the binders on and steer out of trouble.
--
Tekkie

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wrote:

And that doesn't even work when you get into sloppy wet slush - The brakes basically shut off, and if you could steer around the trouble you wouldn't need to even try the brakes.
When driving in those conditions you drive as if you have no brakes - because when it comes right down to it, you will be right.
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On 20/01/2018 9:05 AM, Clare Snyder wrote:

Otherwise known as defensive driving!
I like your thinking! ;-)
--

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Clare Snyder posted for all of us...

to

+1 Training to steer out of trouble is hard. One has to focus their eyes on where they want to go rather than latching onto the collision site.
--
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On Mon, 15 Jan 2018 14:27:23 -0500, Clare Snyder wrote:

Except that Axxis marketing told me, personally, that all these words are marketing bullshit (he used nicer terms than that).
Do you think I don't call these people up when I have their numbers?

Hmmmmhmmmhmmm... this is interesting. I like it! If the test works, that's a nice test. I'm gonna have to bring a magnet with me to the web when I look them up online! :)
Seriously though, it's nice if the pad is in your hands. I'll bring a magnet with me if I end up buying them from the parts store. And I can test the old shoes and pads when I take them off.
Good idea if it works. Can others concur it works?

The Ameca engineer talked about 1st tier but he wouldn't tell me which companies that is, so I don't know what you know.
He did say that aftermarket makes only a handful of formulations that they fit to all cars.

That's like saying you decide the characteristics of a wife, and then go and marry her. It's not extrapolatable with the information you have.
It's just not.
And you seem to buy on a number line, like most people, and that's fine, for you. I like to buy by specs, and they just don't exist.
SO I'm fucked.

Of course. That's a given that the hardware needed is there, and that it fits. In the case of the Toyota drums, the only hardware needed for sure is the U clip which has to be bent. The OE pads come also with circular retainers.

You missed what I said, or I didn't say it right. Specifications are not bullshit. Marketing spin is bullshit.

The science is only in the hands of the formulators. Nobody else has access to that science.

This is good to know because Rock Auto has really low prices! They were so low, they scared me. That's how low they were.

I don't have any paranoia. You *think* I do, and that's fine. But I don't. I just don't trust marketing as much as you seem to trust them.

That's a good question. The AMECA engineer said only the OEMs spend the immense time to get the formulation right. So that would say that, if you like what the OEMs did for you, that you should pay the $157 for OEM FF shoes and not the $20 for aftermarket FF shoes.

In the case of Toyota, it's Nisshinbo Automotive Manufacturing, Inc.
But you bring up a good point, which is what the AMECA engineer said, which is to buy "regionally" if you don't go OEM.
His algorithm was to buy a brand from the same region as where your OE shoes were made. If OE is from Germany, then buy a German-built pad. If OE is Japanese, then buy a Japanese pad.
He didn't explain in detail why, but his point may be the same as yours, which is that there aren't a whole lotta' manufacturers out there, but luckily, with the AMECA Edge Code, we know the manufacturer of *every* brake pad out there, and the code for the specific material.

I *hate* not being able to make an intelligent choice based on specifications. I just hate it.
And, you just can't make an intelligent choice based on specifications for brake pads because all you really know are who made it, what it's friction is, and whether the compound is exactly the same as another.
That's not enough to make an intelligent comparison. And you never will have the capability to test them scientifically.
So we're all blind - although most people don't seem to realize they're blind.

I've had Jurid, Textar, Akebono, and PBR on my car. They're all the same to me. The first week they feel vastly differently, then the same forever more.
The first week, we're comparing old pads to new pads, mind you.

Yes. I know. Everyone knows that. Even non engineers. But my point is that it wasn't obvious until Gallileo tested it. So millions of people thought otherwise, because intuitively it seems that it woudl be the case.
You knew that. A feather and a bowling ball will fall differently, in air, but the same in a vacuum. We all know that.
My only point there was that intuition is almost always wrong. Anyone who trust their intuition, is almost always wrong.
Don't even get me started on high-octane claims in commercials.......

Yup. That's the only logical conclusion anyone can make using Occam's Razor.
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On 1/15/18 8:28 PM, Mad Roger wrote:

On the rare occasions I do my own brakes, I use either NAPA, Warner or OEM parts. Not whatever is cheapest at Auto Zone, JC Whitney or Pep Boys.
The rest of the time I just take the vehicle to a reputable mechanic and tell him what I want. It gets done right.
All your blathering is like arguing with your doctor, "But I read on Facebook (or WebMD)."
--
"I am a river to my people."
Jeff-1.0
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On 16/01/2018 1:48 PM, Fox's Mercantile wrote:

May the Lord save us from those who *think* they know!
--

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On Tue, 16 Jan 2018 02:28:52 -0000 (UTC), Mad Roger

from the PBR brake site :
PBR Axxis Metal Master Brake Pads, Ultimate Brake Pads, and Deluxe Brake Pads
Note: The FMP Group Australia Pty. Ltd., is the manufacturer of Axxis and PBR brand brake pads; these pads are identical.
Axxis Ultimate Brake Pads
Ultimate
The PBR Axxis Ultimate brake pads feature a special Kevlar® and ceramic-strengthened formula with a high co-efficient of friction and excellent high temperature wear and fade resistance. Designed for ultra-high performance driving and hard-braking applications, PBR Axxis Ultimate pad users will benefit with extreme stopping power and high resistance to brake fade at high temperatures, meaning the decrease in friction over repeated heavy duty stops, as the temperature increases, is minimal. PBR Axxis Ultimate pads boast a maximum continuous working temperature of 550° C (1022° F degrees). Consistent throughout its operating temperature range, you’ll get dependable, predictable stops time after time while maintaining a solid pedal feel.
Axxis Metal Master
Metal Master
Metal Master: Non-asbestos, semi-metallic compound provides the highest fade resistance among leading semi-met brake pads. They deliver proven longer pad and rotor life, with low rotor scoring and quiet braking. •Designed for applications requiring the highest performance •Premium quality, non-asbestos, semi-metallic formula •Unique formula offers reduced brake dust, fade and squeal •Provides the ultimate stopping power under all conditions •Virtually eliminates squeal and dust •Improved cold effectiveness •Improved pad life
Axxis Deluxe
Deluxe
Exclusive OE equivalent organic compound provides outstanding stopping power with very low fade. Extremely quiet with proven long pad and rotor life and low rotor scoring. Provides measurably longer life and has extreme resistance to heat while delivering consistent, smooth braking performance. •Formulated from the latest premium quality, organic materials •Low dust, low squeal •Delivers quality braking performance •Rotor friendly •Smooth stopping power •Low dust and squeal •Extended pad life Get yourself a set of PBR Axxis Ultimate, Metal Master, or Deluxe pads today! Brake pads! High Performance Brake Pads! Theres nothing better for braking performance than a good brake pad.
So PBR makes 3 differentlines of brakes. One is sold as AXXIS Ultimate, oneas Axxis Metal Master, and one as Axxis Deluxe. (Also sold underthe PBR brand)
3 totally different pads for diufferent use - all spelled out on the PBR brake products web site. If you spoke to a PBR marketing person you spoke to an idiot who doesn't know their product line, and knows even less about brakes. What you got from HIM WAS marketing bullshit.

Whoever you called gave you VERY bad information.

And you are still stupid enough to think you have to buy online -- I just cannot figure you idiots out.

But metallics are not NECESSARILLY magnetic - because they can be copper or brass - and even ceramics can have some metal in them - as can some organics. You just DON"T GET IT.

Get used to it.

Which is pure bull;shit when talking about tiuer one aftermarket suppliers (which are also OEM suppliers in most cases)

I do NOT buy on a "number line" - I buy by spec. I buy organic, semi metallic, or ceramic depending on what brake characteristics I need and what I'm willing to pay.

You've done it to yourself.

You keep going between pads and shoes. There is so much difference - hardly oranges to oranges - barely apples to oranges - more like rutabagas to apples.

ANd I don't look at "marketing spin" I look at "real" specifications. What KIND of brake material is it? Knowing the KIND of material I can pretty accurately deduce the basic qualities of the brake product - and knowing the manufacturer AND the composition, I can make a pretty good deduction as to quality and suitability for my purpose. Without any "number line" or "friction rating"

And where do you get the idea I trust "marketing"?????

No, for the Toyota you buy Akebono brake shoes - the aftermarket supplier that also produces the OEM brakes for a large percentage of Toyota vehicles (Toyota generally "dual sources" all major parts that the source from outside, like brakes, shoicks, lenses, bulbs, and spark plugs. If one supplier has a problem they cut them off until the problem is solved. (for spark plugs it was always either Nipon Denso or NGK,, foir many parts like AC it was Aisin or Denso.
The MAJOR Tier one aftermarket suppliers are also major OEM suppliers.
TRW, Walker,Monroe, Delphi, and a host of other manufacturers design and build all kinds of parts for the OEM market - as well as the aftermarket.

That will be ONE of their brake suppliers.

Then what are yopu fussing about????????

Not if their "intuition" is "educated"

ANd you know NOTHING about octane and detonation - I'd be willing to bet significantly on that one. (Few people do - the myths on that subject are - well - "mythical".
Don't get started on that one unless you want to get TOTALLY buried......

Why use Ocam's razor - don't you have your own????
Seriously - you are making more assumtions than I am - therefore the chances of your conclusions being correct are significantly less than mine.
Not quite sure you fully understand "Ockham's Razor" either (also known as Occams razor - not Ocams) - a theory first postulated by a 14th century mathemetician and Franciscan Friar by the name of William of Ockham as part of his "unified field theory"
His principal is simply "Entities should not be multiplied unnecessarily."
It has been expanded on by many others includingsuch natables as Einstein
Like any sharp instrument -Ockhams razor should not be weilded blindly - - - -
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On Mon, 15 Jan 2018 09:43:16 -0800 (PST), trader_4 wrote:

I removed s.e.r so I didn't see this post until moving over to a.h.r, so I apologize for not having prior responded.
I agree with you on pedal force, where we must note that the range was from about 8 foot pounds to about 30 foot pounds, from a slow deceleration to a panic stop, which I presume we're all able to supply.
I'm not defending the police report but they did mention that women are in the force now, and they mentioned that they cruise all day, but still, I'm with you on the pedal force.
To their credit, the pedal force *does* equate to stopping distance, where only the 30 foot pound panic stop test actually stops in the *shortest* distance possible.
Fundamentally, what they found was that the pedal force between any two pads (all were either EE or FF) varied by about 10 foot pounds (give or take) to keep to a given deceleration, which, I'm guessing, isn't all that much of a difference that is meaningful to us.
Still ... it's the best test we could find, so if you can find a better test, we'd be all ears.
As for your last comment that 'friction is a red herring', I can't logically disagree (given the facts we've unearthed), but intuitively I would have *assumed* that friction was of primary importance in brake friction materials.
Given that intuition fails in this case, it's one reason why I say that most people who *only* rely on intuition are more often wrong than right, because in this situation, clearly, friction isn't of primary importance in brake friction material performance.
Who knew. Only Clare. Certainly not I.
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On Sun, 14 Jan 2018 17:58:04 -0800 (PST), snipped-for-privacy@gmail.com wrote:

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! :)

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.

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?

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.

Or rubber in bicycle brakes.
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On Mon, 15 Jan 2018 14:19:40 -0000 (UTC), Mad Roger

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.

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.

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.

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

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

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 - - - - .

Not necessarilly.

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

again, bushels of bovine excrement.

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

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!!!

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)
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wrote:

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wrote:

And here is some more real good information on brake pad materials - on a lower level - for the non-engineers out there.
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On Monday, January 15, 2018 at 10:34:19 AM UTC-10, Clare Snyder wrote:

can

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I just picked up a VW door latch assembly on eBay. It's a large electromech anical component that fails frequently. The new part was probably made in C hina but I suppose it could be made in some European shithole country. It l ooks solid enough and I can't imagine that it could possibly be more unreli able than a genuine VW part - whatever the heck that means. It cost me $23, including shipping. I just saved $130.
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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/understanding-friction-and-formulations/
and
http://www.mdpi.com/2075-4442/4/1/5/htm
and
http://www.marathonbrake.com/products/varied-application/ub/
and
https://info.ornl.gov/sites/publications/Files/Pub57043.pdf
and
a whole lot more!!!!!!!!!!!
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