What's the tale of ceramic brakes?

I'm not familiar with ceramic brakes, but they come with a lifetime warranty.
Are they really that good? Do they threaten any other brake system
components? Do they really last forever? Any informed comments appreciated.

On 4 Mar 2020 21:08:58 -0500, wrote:

> I'm not familiar with ceramic brakes, but they come with a lifetime warranty.
> Are they really that good? Do they threaten any other brake system
> components? Do they really last forever? Any informed comments appreciated.

Ready to be shocked?

What do brake pads do?
o HINT: friction, right?

*So what's the friction coefficient (cold/hot) of those brake pads?*

Xeno and others know more than I do, but I've researched how to choose
automotive brake friction materials, even down to calling the PBR and
Metalmaster & Axxis (all the same company!) and Centric and Zimmermann,
etc., marketing guys.

What they told me will shock you, but when I tell it to you, you have to
sit back and have an "Aha" moment, because the sad truth is that the claims
on consumer focused automotive braking friction materials is far more
marketing than truth.

An example of the cold hard unabashed truth?
o The word "Ceramic" in friction materials is nearly meaningless.

The Axxis and Centric marketing guys told me they can sprinkle a bit of
pixie dust into the mix, and "Voila!", it's ceramic!

And, the warranty is a marketing gimmick also.

Just like with consumer automotive batteries and automotive tires:
o The warranty does not track performance (it tracks price better).

The good news is every single brake pad sold in the US for passenger use
has a code stamped on the side which tells you the cold and hot tested
friction rating. Every single one.
o EE === about the same friction coefficient as steel on steel
o FF, GG, HH, etc.

Now, you'd "think" that friction rating equates to stopping distance, but
it's not _that_ simple either. Sigh.

We have a looooong thread on this somewhere, which we can dig up for you:
o <http://tinyurl.com/rec-autos-tech>
o <http://rec.autos.tech.narkive.com>
--
Usenet is so much more valuable, and pleasant, when people act like adults.

wrote:
> I'm not familiar with ceramic brakes, but they come with a lifetime warranty.
> Are they really that good? Do they threaten any other brake system
> components? Do they really last forever? Any informed comments appreciated.
>
>

The big thing with them is that the materials used don't leave the ugly
rust colored crap on the rims. If your vehicle came with them, keep
using them.

They do tend to wear longer, however much of that depends on how you use
the brakes. Constant stop and go gets you increased wear. They don't
last forever, but I have seen sets with 60K on them that still had a lot
of pad left.


--
Steve W.

On Thu, 05 Mar 2020 04:03:24 -0500, Steve W. wrote:

> The big thing with them is that the materials used don't leave the ugly
> rust colored crap on the rims. If your vehicle came with them, keep
> using them.

Let's think about that dust for a moment, taking into account that all pads
dust and all rotors dust (where does all that worn material go anyway?).

I, personally, do _not_ have the answers: I only have questions.

There's a lot of discussion "what" that "rust colored crap" is,
particularly on the bimmer forums where the OE Jurid/Textar pads dust like
hell, and therefore they're often replaced by ATE or Akebono pads which
seem to dust far less.

All pads dust, so one argument is that the dust is simply the "coloring"
pigments in the pads themselves; but the friction material marketing folks
tell me that "rust" color is a clue; it's the metal of the rotors doing the
dusting.

While we'd all agree that both pads and rotors wear, so the "dust" is going
"somewhere", nobody really seems to know for sure "what" causes some pads
to dust more than others, given the same rotors (usually Brembo).
--
Usenet is so much more valuable, and pleasant, when people act like adults.

In article >, > wrote:
>I'm not familiar with ceramic brakes, but they come with a lifetime warranty.
>Are they really that good? Do they threaten any other brake system
>components? Do they really last forever? Any informed comments appreciated.

Pretty much all pads have some "ceramic" elements in them. The ones that
are advertised as "ceramic" are usually low dust and relatively noisy.

They don't have to last forever, they only have to last long enough for you
to lose the paperwork that came with them. They don't last any longer than
any other brakes on the whole. But the manufacturers have worked out that
most people won't save the paperwork or for some other reason will never
take them up on the warranty when they fail.

If you want long-lasting brakes, ask taxicab owners what they use.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Arlen Holder wrote:
> On Thu, 05 Mar 2020 04:03:24 -0500, Steve W. wrote:
>
>> The big thing with them is that the materials used don't leave the ugly
>> rust colored crap on the rims. If your vehicle came with them, keep
>> using them.
>
> Let's think about that dust for a moment, taking into account that all pads
> dust and all rotors dust (where does all that worn material go anyway?).
>
> I, personally, do _not_ have the answers: I only have questions.
>
> There's a lot of discussion "what" that "rust colored crap" is,
> particularly on the bimmer forums where the OE Jurid/Textar pads dust like
> hell, and therefore they're often replaced by ATE or Akebono pads which
> seem to dust far less.
>
> All pads dust, so one argument is that the dust is simply the "coloring"
> pigments in the pads themselves; but the friction material marketing folks
> tell me that "rust" color is a clue; it's the metal of the rotors doing the
> dusting.
>
> While we'd all agree that both pads and rotors wear, so the "dust" is going
> "somewhere", nobody really seems to know for sure "what" causes some pads
> to dust more than others, given the same rotors (usually Brembo).

The brake dust is simply the mix of pad debris and iron from the rotors.
Semi- metallic pads are just that, iron and other metal powders mixed
into the various resins and binders that make up the pad. Go visit a
salvage yard and look at brakes that have been setting unused for a
while, you can see them rotting apart and crumbling. That is because of
the heat they generate while in use baking the moisture in and on them
away so they don't corrode in use.

--
Steve W.

On 5 Mar 2020 10:44:12 -0500, Scott Dorsey wrote:

> But the manufacturers have worked out that
> most people won't save the paperwork or for some other reason will never
> take them up on the warranty when they fail.

WARNING: Everything I say below is "IMHO" as an overall disclaimer since I
am _not_ a brake friction coefficient mechanical engineer.

My "wisdom" on warranties is that anyone who compares by warranty...
o Is simply proving they know absolutely nothing about the product.

I think warrantee's, IMHO, are for people who don't understand the product.
o People _desperately_ desire (a) good, (b) better, and (c) best

Everyone wants a number line to compare good, better, & best.
o MARKETING is perfectly happy to give people a false numberline.

Rather than compare the product on actual performance metrics...
o Marketing tricks them into comparing (meaningless) warranties.

MARKETING is _happy_ to give people a "linear" way to compare product
o By warranty, they can even have you compare to the competitor's warranty!

All without even once looking at what makes the product work
o For example, without looking at the friction coefficient for brake pads

The point is warranty has _nothing_ whatsoever to do with the product.
o There is only one time, and one time only when you care about warranty.
(And that's when you _know_ you're gonna abuse the product.)
Otherwise, the warranty is worthless except under the tie-breaker rule.
o If two products are EXACTLY alike in all other things...
Then, and only then, does the warranty many _any_ difference whatsoever.

I've concluded, long ago, that these so called warranties, are (mostly)
worthless for a variety of reasons, one of which you touched upon
o First, is that the warranty has _nothing_ to do with performance
o Second is, as you noted, you often need to have pristine paperwork
o Another is you generally have to be the original owner (why?)
o Another is they generally pro rate where it's not always linear
o Worse, they often don't give you any sales price when they pro rate
o And, you (often) have to buy the _same_ item
(Wait a minute ... isn't that the items that failed prematurely?)

> If you want long-lasting brakes, ask taxicab owners what they use.

Clare Snyder brought up the "fleet report" from the Michigan Police
Department, who tested brake pads for the fleet vehicles (which taxis are
also).
o Need help INTERPRETING these test results police cruiser SAE J866a Chase Test
<https://groups.google.com/d/msg/alt.home.repair/6UnnUUIMMrM/zI-RmXGsAwAJ>

There is only one thing, and one thing only, that is _reliable_ that a
consumer can go by, which is the friction coefficient (e.g., I'd never buy
less than an FF and I'd prefer a G or an H in most cases).

Everything else that is printed on the box is, IMHO, worthless marketing.
o If you _must_ have a good, better, best, "most" people might recommend:
a) good === non asbestos organic
b) better === semi metallic (or ceramic?)
c) best === ceramic (or semi metallic)

But that's all marketing BS since they can sprinkle pixie dust and call it
anything they want to call it. I've spend more than a few hours on this
topic with the marketing guys, mostly at Axxis/PBR/Metalmaster & Centric.

The _only_ guy who knows _anything_ about the brake pad is the guy who
certified it for the DOT and who therefore gave them the FF, GG, HH,
whatever friction code (plus a few other things about the material).

The rest of us have _nothing_ to go on other than boy-racer bull****
reviews (almost all of which are never on the car you own, driven on the
roads you drive, and driven the way you drive it).

In the end, all you have are two things, and two things only:
1. The friction coefficient, and,
2. Your personal experience (if you've used those brake pads on that car)
--
Usenet is so much more valuable, and pleasant, when people act like adults.

On Thu, 05 Mar 2020 12:20:19 -0500, Steve W. wrote:

> The brake dust is simply the mix of pad debris and iron from the rotors.

Hi Steve W.,
I'm not gonna disagree since what else _can_ it be?
o Brake dust
o Iron dust

> Semi- metallic pads are just that, iron and other metal powders mixed
> into the various resins and binders that make up the pad.

Yes. And no.
o They can sprinkle a bit of metallic pixie dust & call is semi-metallic.

What matters is stuff that you can measure - and stuff you can't measure.
o The friction coefficient you can measure 'cuz it's printed on the pad

Everything else you can't measure even though they're still important:
a. noise
b. feel
c. wear

It's sad, but the _only_ thing that is "reliable" about choosing brake pads
is the friction coefficient printed on the pad itself.

Everything else is subject to marketing bull****, such as the warranty.

> Go visit a
> salvage yard and look at brakes that have been setting unused for a
> while, you can see them rotting apart and crumbling. That is because of
> the heat they generate while in use baking the moisture in and on them
> away so they don't corrode in use.

I'd love to read a scientific paper about what causes all that dark dust.

I'm on a lot of car forums where the one thing I've never been able to
ascertain is why don't _all_ pads cause the dark dust, given that we don't
use stainless steel rotors in normal automotive use.

So the iron from the rotor should _always_ be there, even if the brake pads
dust with different coloring (the lighter the better of course).

Clearly, my bimmer dusts like crazy with the FF Textar pads, less so with
the FF Jurid, but even less so with the FF Akebono or FF PBR pads.

Why?

I've never been able to figure out why, given the rotors are Brembo in all
cases, and they're not stainless steel rotors.
--
Together we can accomplish far more than anyone of us can alone.

Arlen Holder > wrote in
:

> On 5 Mar 2020 10:44:12 -0500, Scott Dorsey wrote:
>
>> But the manufacturers have worked out that
>> most people won't save the paperwork or for some other reason will
>> never take them up on the warranty when they fail.
>
> WARNING: Everything I say below is "IMHO" as an overall disclaimer
> since I am _not_ a brake friction coefficient mechanical engineer.
>
> My "wisdom" on warranties is that anyone who compares by warranty...
> o Is simply proving they know absolutely nothing about the product.
>
> I think warrantee's, IMHO, are for people who don't understand the
> product. o People _desperately_ desire (a) good, (b) better, and (c)
> best
>
> Everyone wants a number line to compare good, better, & best.
> o MARKETING is perfectly happy to give people a false numberline.
>
> Rather than compare the product on actual performance metrics...
> o Marketing tricks them into comparing (meaningless) warranties.
>
> MARKETING is _happy_ to give people a "linear" way to compare product
> o By warranty, they can even have you compare to the competitor's
> warranty!
>
> All without even once looking at what makes the product work
> o For example, without looking at the friction coefficient for brake
> pads
>
> The point is warranty has _nothing_ whatsoever to do with the product.
> o There is only one time, and one time only when you care about
> warranty.
> (And that's when you _know_ you're gonna abuse the product.)
> Otherwise, the warranty is worthless except under the tie-breaker
> rule. o If two products are EXACTLY alike in all other things...
> Then, and only then, does the warranty many _any_ difference
> whatsoever.
>
> I've concluded, long ago, that these so called warranties, are
> (mostly) worthless for a variety of reasons, one of which you touched
> upon o First, is that the warranty has _nothing_ to do with
> performance o Second is, as you noted, you often need to have pristine
> paperwork o Another is you generally have to be the original owner
> (why?) o Another is they generally pro rate where it's not always
> linear o Worse, they often don't give you any sales price when they
> pro rate o And, you (often) have to buy the _same_ item
> (Wait a minute ... isn't that the items that failed prematurely?)
>
>> If you want long-lasting brakes, ask taxicab owners what they use.
>
> Clare Snyder brought up the "fleet report" from the Michigan Police
> Department, who tested brake pads for the fleet vehicles (which taxis
> are also).
> o Need help INTERPRETING these test results police cruiser SAE J866a
> Chase Test
> <https://groups.google.com/d/msg/alt....MrM/zI-RmXGsAw
> AJ>
>
> There is only one thing, and one thing only, that is _reliable_ that a
> consumer can go by, which is the friction coefficient (e.g., I'd never
> buy less than an FF and I'd prefer a G or an H in most cases).
>
> Everything else that is printed on the box is, IMHO, worthless
> marketing. o If you _must_ have a good, better, best, "most" people
> might recommend: a) good === non asbestos organic
> b) better === semi metallic (or ceramic?)
> c) best === ceramic (or semi metallic)
>
> But that's all marketing BS since they can sprinkle pixie dust and
> call it anything they want to call it. I've spend more than a few
> hours on this topic with the marketing guys, mostly at
> Axxis/PBR/Metalmaster & Centric.
>
> The _only_ guy who knows _anything_ about the brake pad is the guy who
> certified it for the DOT and who therefore gave them the FF, GG, HH,
> whatever friction code (plus a few other things about the material).
>
> The rest of us have _nothing_ to go on other than boy-racer bull****
> reviews (almost all of which are never on the car you own, driven on
> the roads you drive, and driven the way you drive it).
>
> In the end, all you have are two things, and two things only:
> 1. The friction coefficient, and,
> 2. Your personal experience (if you've used those brake pads on that
> car)

EXcept the brake coefficient is not a straight item either, you can
have brake pads with great coefficient but short life, or almost the same
coefficient but much longer life, because of the materials they are made
of, so your idea is not quite correct. material compisition is VERY
important to the consideration. not just the coefficient specs. KB

On Thu, 5 Mar 2020 20:45:23 +0000 (UTC), Kevin Bottorff wrote:

> EXcept the brake coefficient is not a straight item either, you can
> have brake pads with great coefficient but short life, or almost the same
> coefficient but much longer life, because of the materials they are made
> of, so your idea is not quite correct.

Hi Keven Bottorff,

I _agree_ with you fully & completely.

For example, as we covered long ago on this newsgroup, fleet vehicle EE
pads seem to outperform FF pads in this police cruiser study done in 2000!
o <https://www.justnet.org/pdf/EvaluationBrakePads2000.pdf>

So even these reliable hot/cold friction coefficients aren't much to go by.
o AMECA Compliance List of Automotive Safety Devices: Friction Material Edge Codes(TM), May 2011
<http://safebraking.com/wp-content/uploads/2013/02/AMECA-List-of-VESC-V-3-Brake-Friction-Material-Edge-Codes-May-20112.pdf>

*But it's all we got, unfortunately.*

IMHO... everyone desperately wants a good/better/best number line!
o But that good/better/best number line just doesn't exist for brake pads.



> material compisition is VERY
> important to the consideration. not just the coefficient specs.

No doubt material composition is critical to _everything_, e.g.,
o noise
o dusting
o wear
o fade
o vibration
o friction
etc.

The problem is that the _only_ thing we have to go on that is _reliable_ is
the friction code, and our own personal experience (which isn't much if the
brake pad isn't one we've _already_ tested in that exact vehicle driven
under the exact conductions by the exact same driver, etc.).

My main point is that we don't have much to go by for choosing pads
o Going by marketing claims is foolhardy in my humble opinion
o So is going by warranty (what does that have to do with performance?)
o Also is "trying" to go by "boy racer reviews" (most are worthless, IMHO)

Unfortunately, since Marketing can claim "ceramic" simply by sprinkling a
meaningless bit of clay into the mix, even the age-old distinctions are
"nearly" worthless, IMHO:
o non-asbestos organic
o semi-metallic
o metalic
o ceramic
etc.

All we have are the friction coefficients that we can at least rely upon.

All is not lost though, since I'm of the opinion that _all_ brake pads will
work fine, where, what I do, for any given make & model, is read the forums
on that make & model.

For example, a _lot_ of the bimmer guys went for the Duralast battery when
it was available from Autozone instead of the BMW battery, as just one
example. It was the de-facto battery to use by almost all accounts.

Same with friction materials, where the old time E39 folks go for PBR over
the OE Jurid/Textar pads, for example, on plain steel Brembo rotors, where
only the "boy racers" are the ones who suggest the "fancy" stuff on the
even fancier bling drilled and slotted rotors - and then - they claim that
their braking improved fantastically.

In summary, I agree with all sensible claims above, where the OP asked
about warranties, and where my advice to the OP is simple:
1. Find out what the OE pads are (brand & friction rating)
2. Buy nothing _less_ than that friction rating.
3. At the cheapest price you can get them for.

That's _my_ advice, where I've _studied_ this problem set for decades.
DISCLAIMER: I'm not a mechanical engineer so take my advice with NaCl.
--
Together we can learn far more than anyone of us can by learning alone.