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

The shoes they tested were premium and heavy duty (all of the FF and FG were "heavy duty" pads.

On Persuit rated vehicles they oftern also have larger rotors and drums - as well as different tires, and even different RIMS to allow bwtter brake cooling. Never wondered why cruisers have "dog dish" hub caps instead of full wheel covers??? To allow the brakes to "breath" better.

I can say without reservation that the "police duty" and severe duty brakes were MUCH better at high speeds than standard brakes (and sometimes not nearly as good when cold/low speed) 1 1966 Dodge Polara Pursuit Special I drove for a short time went like a scalded cat, and stopped like you had jammed a stick into a hole in the pavement.

Yes.

Todays persuit special vehicles are often the big ecoboost engine on fords, and Hemis on Chargers. Often with a "special tune" that raises the rev limiter setting and reprograms the tranny shift points - as well as having bigger rads, bigger alternators, honking big sway bars and super-duty shocks and springs.

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)."

Most definitely is NOT marketing Bullshit. It is solid engineering

You speak mandarin, do you? There may not be "legal" definitions, but there are industry accepted definitions - and I've sent you numerous referencesthat spell them out pretty clearly. Yes, there are "hybrids" that sort of bridge the gap - but MOST of them are identified as such.

Most definirely not. There is a small percentage of metal even in organic pads, and the metal does not need to be iron. And "ceramic" has nothing to do with "dust".

A ceramic is a vitified clay base which may or may not have metals also included. A ceramic does not use phenol;ic binders.

Again - READ the stuff I posted for you.

You are being a paranoid simleton.

And YOU think YOU are smart. (nobody else does - sorry to break your bubble)

and if you are SMART you buy the type of pad that matches yourdriving requirements - which for most commuters is a standard organic pad, for heavy duty use, a semi metallioc, and for high speed light duty, generally a ceramic.

And yet you most certainly do NOT when it comes to brakes. You are totally clueless and uneducatable

and you seem to be totally incapable of it.

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

I caught on to that very early in the piece. That's why I deduced that discussion with mad roger was not a fruitful use of my time.

As you have discovered.

Amen to that! Just wants to argue the toss, that is all.

He is.

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 - - - -

If I know my application jolly right I can

You obviously did not read and absorb the details of the michigan test. All the brake fade data is clearly there if you know how to read the report.

i CAN TELL YOU which brake pad is going to fade the worst, just knowing the COMPOSITION of the pad - organic, semi-metallic, or ceramic - particularly between products from the same manufacturer. WHos ceramic is beter than whos is a different story - -0 -

I can know who made them and what market theyn are aimed at - which gives me a lot more information than their 2 letter friction rating.

You are a total MORON

AXXIS and PBR ARE the same company, but a PBR or AXXIS Metalmaster is NOT the same as a PBR or AXXIS Delux or Advanced Ceramic - but PBR/AXXIS has more marketing BS than many companies.

well, I know from dealing with brake application engineers and my studies that "marketing guys" are generally like a dirty diaper.

You seam like someone who doesan't know the questions to ask, doesn't know when he's being snowed, and is so obvious that the marketing guys know they can snow you and you won't know the difference. When you need technical information you don't ask marketing - you ask engineering - and you don't go in like a smartass - they can see right through you.

The marketing guy doesn't know shit from shinola

I'll agree to allow you to remain eternally clueless since you are totally unteachable.

Just like a dirty diaper.

AXXIS delux pads are the same as PBR delux pads, but are NOT the same as AXXIS or PBR Metalmasters - and "Metalmaster" is not a company or resller - it is a "model" or "type" iof pad marketted by AXXIS , a devision of PBR PLC in Australia.

A warranty is an insurance policy - not an indicator of quality. How else do you explain a 10year warranty on the shittiest cars to come out of Japan - the MisuShitty. They can't sell their crap without a

10year warranty - and when the warranty is expired you can't sell one

- period.

Yad yada yada---------

Sure I do

Well, he was WRONG.

Most certainly NOT everybody knows it.

Not neccesarily - If caught on time it is almost always reversible

You are a thickskulled and stubborn person - totally unteachable

WRONG - his livelihhod depends on it

Wrong. As a professional mechanic of long standing, with an EXCELLENT reputation, I take that as a total affrront

I've seen the same forums - and most of the compainers are just as dumb as you are.

You are free to do it yourself on your own car - although I don't plan on being anywhere near you - but you should NOT be doing repairs on other peoples vehicles - you are untrained, unauthorized, and uninsured.

Anyone letting you work on their vehicles should be made aware of that, and the dangers implied.

Ignorance is no excuse.

Well, you would be wrong.

Wrong again.

PLONK

I'm reading them as soon as I post this to let you know that... Thanks for always posting on-topic technical value.

Yup. Basic Economics 101. Price is only a function of demand.

Price is never directly related to quality. Price is only a function of demand.

Demand is a function of lots of complex variables, which is why they invented Marketing (to greatly influence the demand).

I can't imagine buying used brake shoes or pads off a scrapped car. I just can't.

Whoever proposes to buy brake pads and shoes off of junked cars is fine with his logic, but he doesn't need to repeat it since it's not something most of us would do.

I can see buying some parts at a scrap yard (e.g., a door or a fender), but I just can't see buying a brake pad or shoe off a scrapped car.

How do you even do that? Do you walk around the junk yard to look for your exact year, make and model and then pull the wheels and then pull the pads?

That's a lot of work, if you even find the right make and model, and then if you can get to it (since they pile these things five cars high sometimes) and if you can get the rusted lug bolts and brake drums off and then you have to disassemble the brakes.

Seems like a *lot* of work for a brake shoe that will be "iffy" because you have no way of knowing their condition ahead of time.

Or, maybe the junk yard does that for you, but then you are just staring at a pile of brake shoes on the wall, which maybe, if you're lucky, have accurate designations for the make and model of the vehicle they came off of.

I guess if you bring your old shoes with you, you can match them, but that means your car is on blocks the whole time you do this, so you have to have a second vehicle to do it.

I just don't see *how* it's practicable. Do you?

Yup. Basic Economics 101. Price is only a function of demand.

Price is never directly related to quality. Price is only a function of demand.

Demand is a function of lots of complex variables, which is why they invented Marketing (to greatly influence the demand).

I can't imagine buying used brake shoes or pads off a scrapped car. I just can't.

Whoever proposes to buy brake pads and shoes off of junked cars is fine with his logic, but he doesn't need to repeat it since it's not something most of us would do.

I can see buying some parts at a scrap yard (e.g., a door or a fender), but I just can't see buying a brake pad or shoe off a scrapped car.

How do you even do that? Do you walk around the junk yard to look for your exact year, make and model and then pull the wheels and then pull the pads?

That's a lot of work, if you even find the right make and model, and then if you can get to it (since they pile these things five cars high sometimes) and if you can get the rusted lug bolts and brake drums off and then you have to disassemble the brakes.

Seems like a *lot* of work for a brake shoe that will be "iffy" because you have no way of knowing their condition ahead of time.

Or, maybe the junk yard does that for you, but then you are just staring at a pile of brake shoes on the wall, which maybe, if you're lucky, have accurate designations for the make and model of the vehicle they came off of.

I guess if you bring your old shoes with you, you can match them, but that means your car is on blocks the whole time you do this, so you have to have a second vehicle to do it.

I just don't see *how* it's practicable. Do you?

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?

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.

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.

Naah. I took the class. I got an A. If it's "elastic", it follows the supply and demand curve, where prices are set based purely on demand.

If it's not elastic, then all bets are off.

Marketing's job is to make things non elastic, and they do a great job of that, given, for example, people seem to wait in long lines just to spend twice as much on an iPhone as it's actually worth.

Assuming it's perfectly elastic.

Nobody said otherwise. If there's something "different" (even the color for example), then it's different.

What you seem to be discussing is the difference between a commodity (where even the color is unimportant), and the opposite of a commodity:

The curves are completely different in their elasticity. A brake shoe "should" be a commodity (but might not be).

Again, same concept as above. Those are three different things because demand is different for them. There could even be a curve for Australian versus British Prime Steak.

If it were a commodity, then the curve is more elastic than if it's not.

Nobody ever said the curves aren't different for different products. They can even be different in different locales. For example, whale steak may have a different curve in Japan than in India.

Nobody ever said that each product has its own supply and demand curves. If you consider a pink iPhone different than a black one, it can have a different curve.

The Marketing people figure all this out for us and price accordingly to get the best marginal utility out of us.

You inferred that. Incorrectly. Nobody said it but you. :)

What we need to discuss is brake pads and shoes.

They would actually have different curves if they were different, or, more to the point, if people *believed* they were different.

For example, if you thought an EE pad was shit (as I did), then it would be worthless to you at any price, even at free. But if you thought an EE pad could be as good as an FF pad at braking, then the curve is completely different.

At the moment, the only logical conclusion anyone can scientifically make, is that all pads we can buy the USA are 'about the same' (give or take) because we have no way of telling them apart if we had both in our hands (or on the web).

In the end, Clare did say pretty much to get any shoe that "says" it meets OEM Quality - so that means all OEM Quality shoes should have the same demand curve.

This is only enginering, logic, and economics. No black art should be involved in buying brake pads and shoes.

You didn't understand a single word I said. Either that, or you just want to argue.

We agree on the curves being *different* for things that are perceived to be different.

If a tire to a billion people is NOT a commodity (there doesn't seem to be a word for the opposite of a commodity), then each one has a certain demand curve.

If those same tires *are* considered a commodity to another billion people, then those tires, to those people, have a *different* (lumped together as one) commodity-based demand curve.

Either you understand that, or you just want to argue for argument's sake. I am done with arguing what is in *every* Economics textbook on the planet.

I can't teach you an entire course in Economics 101 in just a Usenet thread. You either understand the basics, or you don't.

It's marketing's job to increase *perception* of value.

If you like beef and don't like pork, then the curves are different. If you don't care, and if it's all just "meat" to you, then they're not.

This is extremely basic stuff covered in the first weeks of class.

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*.

"antilock brakes just guarantee you will hit whatever you hit SQUARE ON!!!"

LOL, they will indeed!