Brake Pads and SAE J866

[GolfRRRR1]

Brake pads and where to start....or should I say stop!
Interesting thing happened the other day, I was looking at all the threads on brake pads, and began to wonder, instead of using opinions to purchase pads (e.g. I bought brand x pad and and it cost a lot of money so it has to be a great brake pad, so buy what I buy because I bought it). There should be some kind of actual measurement of braking ability of brake pads across the board. A coefficient of friction table with all brake pads for our vehicles so we can cross-reference them to factually compare them, apple to apples.
In my quest to buy stock caliper (Golf R/GTI PP) brake pads, I've read countless websites, manufacturer's MU graph's, tried to cross reference and compare, watched many Youtube videos, it's all just frustrating. Many people here know I bought TRW TPC1633 pads and TRW TXH1633 pads, and I often suggest these pads to people who are looking to replace 'stock pads' with something still good but less dust.
Regardless, in my continued search I came across this article: SAE J866 Friction Codes Here is the list Friction codes list

I then began looking at brake pads and the codes which are mandated by the DOT to be printed on them. Codes are printed on the backing plate or side, if you have brake pads that are not on this list, it's because I didn't find the codes. Bear in mind these are ranges so a pad that gets a cold rating of F may have a coefficient rating of say .44 while a pad with a cold rating of G may only have a friction coefficient of .45 or .46, not much of a difference or the difference could be massive say .35 (lowest F rating) to .55 (highest G rating)

Friction codes:
C = up to .15
D = over .15 up to .25
E = over .25 up to .35
F = over .35 up to .45
G = over .45 up to .55
H = over .55
Z = unclassified

I do have to mention, only EBC Brakes tout their friction rating on their website, they state it many times in the Yellow Stuff (all new formulations in 2021) page and Ultimax2 page.

This is a guide for those looking for a spirited street drive brake pad.

Here are a few that I found: (alphabetical in it's rating)
Stock part #5Q0698151K is rated GG

Brembo P85144 FE
Centric C-Tec FE
Hawk Ceramic HB788Z.745 FE
Pagid 8V0698151C (OEM) FE

Bendix SBC1633 FF
Bosch Blue BE1633H FF
Ferado Racing DS2500 FF
Hawk HPS HB779F.740 FF
Hawk HPS 5.0 HB779B.740 FF
Stoptech 309.16330 FF
Wagner ThermoQuiet QC1633 FF

Bendix CFC1633 GF
Brembo 3C0698151H GF
TRW TXH1633 GF

Power Stop Z23-1633 FG

Bosch QuietCast BC1633 GG
EBC Yellow Stuff DP42127R GG
EBC Ultimax2 UD1633 GG
Hawk HP Plus HB779N.740 GG
TRW Pro* 8V0698151C GG
TRW TPC1633 GG
*also stamped with TPC1633

Cliff Notes for you skimmers: The codes are rated by coefficient of friction, there are 2 codes a (low temp code 200*F-400*F) and a high temp code (300*F-650*F)
So TRW TPC1633 is coded as GG (.45-.55) friction coefficient at low temp and high temps, while a Wagner ThermoQuiet is rated as FF (.35-.45), so it will be a brake pad with less friction coefficient and therefore, less stopping power than the TRW.

Good luck with your quest! More pads to come as I receive more information.

 

[Chubby Bunny]

Got these sitting in living room, thought I could add to your list

Power Stop Z23-1108 FG

Power Stop Z23-1633 FG

​

 

[GolfRRRR1]

Got these sitting in living room, thought I could add to your list

Power Stop Z23-1108 FG

Power Stop Z23-1633 FG

​

Nice! Was looking everywhere for those, waiting for their tech team to get back with me. So, they grip a little more with heat.

 

[DerHase]

Note to self: check DS3.12 And DS1.11 pads when I get back home in a couple days. They're loud and obnoxious track pads, but I'm curious if they have a rating.

While the friction ratings are maybe useful for general feel on the road - what you won't know is:
- at what point do they "fall off" the friction curve?
- how quickly so they fall off? Is it gradual or do you go from feeling pretty good... To nearly nothing?
- is the dust corrosive to wheels/paint etc?
- how well do the pads release from the rotor? (If you have ever tried trail braking with Hawk anything and switched to Carbotech or G Loc or Raybestos you'll instantly figure out why nobody who wants to win runs Hawk stuff).


Now I understand the intent of this thread isn't track pads - but I just wanted to be clear as some people are going to see this and think "oh wow EBC is awesome"... When those are the pads that are well known for the friction coefficient to just drop like a rock when exceeded (which will happen as you pick up speed as a driver).

I have experience with the DS2500s on this car, and HPS 5.0s on some others. Both are pretty good overall. 2500s are trackable with a gradual decline in friction as you exceed their limits. The 5.0s are somewhat similar in feel at the limit, with a softer initial bite.

Most of Hawks compounds are old as dirt. The HPS 5.0 is relatively new (within the last 10 years). I tried the regular HPS once and threw them away and bought factory Mazda pads for the Mazda3 I used to have. HP+ and any of the DTC stuff feel like stepping on blocks of wood feeling-wise, and eat rotors which leaves a nice layer of rust all over the side of your car like it's been parked next to a rail yard for years.



Getting back to street pads: while I've not used them on my GTI, the Carquest/Advances auto Gold or Platinum pads are actually really pretty good for a daily/auto-x budget pad. I've put them on several cars and they're really not terrible. Have NOT tracked with them though so wouldn't recommend that.

 

[RMinNJ]

Looking for stock I went with Pagids. Maybe TRW would have been better?

 

[GolfRRRR1]

Looking for stock I went with Pagids. Maybe TRW would have been better?

The Pagids in OEM form carry an FE code, that doesn't mean they are bad by any means, they just have different friction ratings. These friction ratings are just one standardized test at 2 specific temperatures. They don't speak to how 'grabby' they are, or how they compress, release or fall off at higher temperatures as stated above by DerHase. They don't rate the overall feel, how many feet your Golf will stop in, just two specific friction ratings at the specific temperatures, but yes, all that said, at 200-400 degrees F and 300 - 650 degrees F the TRW TXH1633 have a higher frictional rating of GF. Something else to take note of, even if you have a fantastic feeling C code pad (just for an example), while it will 'feel' great to the driver, it just can't magically create the actual friction of say an E, F, or G pad.

Pagid OEM formulation:
F code = .35 - .45 at low temps (200-400F)
E code = .25 - .35 at high temps (300-650F)

TRW TXH1633
G code = .45 - .55 at low temps (200-400F)
F code = .35 - .45 at high temps (300-650F)

TRW Low-Metallic Pro 8V0698151C
G code = .45 - .55 at low temps (200-400F)
G code = .45 - .55 at high temps (300-650F)

 

[RMinNJ]

Thanks... guess I should have got the TRWs?. I was not familiar with the brand and FCP Euro listed the Pagids as OEM while only one set of TRW for my non PP brake was. They were not the TRW numbers you listed for nonPP size. Think I will hope for the best with the friction rating ..do not track my car or anything.

 

[ZERO815]

Very interesting thread, however as mentioned before 2 data points aren’t enough to judge IMO.
Recently swapped worn OE stuff on my US MK7 PP to Brembo rotors and pads (P85144 pads in front).

In your table they are FE. I took a picture of mine before installation w/ GF on it. Strange huh?

Since I’m in Spain currently, google offered me several pics of P85144‘s from spanish parts websites. Guess what, I found a picture with the same part number but FE on them too.

Of course I don’t have first hand experience with FE and GF pads, or a crazy amount of data points, however I think it’s strange that companies can offer obviously different parts under the same part number!??

 

[GolfRRRR1]

Very interesting thread, however as mentioned before 2 data points aren’t enough to judge IMO.
Recently swapped worn OE stuff on my US MK7 PP to Brembo rotors and pads (P85144 pads in front).

In your table they are FE. I took a picture of mine before installation w/ GF on it. Strange huh?
View attachment 281148
Since I’m in Spain currently, google offered me several pics of P85144‘s from spanish parts websites. Guess what, I found a picture with the same part number but FE on them too.
View attachment 281149

Of course I don’t have first hand experience with FE and GF pads, or a crazy amount of data points, however I think it’s strange that companies can offer obviously different parts under the same part number!??

Yes, they do offer different mixes (environmental and others 1st pic is N22 mix and 2nd N18 mix) and have to stamp them different, that said GF WILL have a higher coefficient of friction, SAE tested and stamped.

 

[Pierreoj]

Adding friction codes for non-PP pads I have installed in the last 2 years.

Front:
- Textar GF (good daily driver pad, quiet, a lot of brown dust but easy to clean)
- Raybestos EHT1760 GH (too grabby, low dust, clunk noise all the time going reverse, inexpensive)
- ATE low dust ceramic LD2785 GH (low dust, great cold temperature friction, great modulation, quiet, “ultra-premium” daily driver pads, expensive)

Rear:
Textar EE
Raybestos EHT1779 GH (inexpensive, great improvement from the Textar, no dust, good cold weather response, occasional clunk when reverse)

 

[enobiko]

My Brembo ceramic rears (P85095N) are stamped GG! I can't see what my matching front pads (P85144N) are stamped, I'd have to pull the calipers off.
My observation: they feel great so far, but I haven't had a chance to really push them hard.

 

[Mr. Conundrum]

THX1633 - HG

TXH1348 - FF

My TXH1633 seem to have a different rating to the ones you listed. Strange, but I'm not complaining about greater low temp friction vs stock.

 

[victorofhavoc]

Keep in mind there's no standardized testing process where manufacturers or anyone dictates the coefficient of friction of a brake pad on specific and consistent measurement patterns. Just because one pad is FF rated doesn't mean it's better or worse than a FG or EE pad. Vehicle weight, weight distribution, and tire will all have different effects on how each pad will work. Pads too aggressive for the tire will actually overheat sooner than pads balanced to the tire.

Where these values can be meaningful is when comparing pads from the same manufacturer during the same pad manufacturing time period...

 

[GolfRRRR1]

Keep in mind there's no standardized testing process where manufacturers or anyone dictates the coefficient of friction of a brake pad on specific and consistent measurement patterns. Just because one pad is FF rated doesn't mean it's better or worse than a FG or EE pad. Vehicle weight, weight distribution, and tire will all have different effects on how each pad will work. Pads too aggressive for the tire will actually overheat sooner than pads balanced to the tire.

Where these values can be meaningful is when comparing pads from the same manufacturer during the same pad manufacturing time period...

You either didn't read the article or understand SAE standardized testing and DOT compliant regulations. The higher a brake pads coefficient of friction, the greater the stopping power (all things being equal) Full stop.

 

[GolfRRRR1]

THX1633 - HG
View attachment 289623

TXH1348 - FF
View attachment 289628

My TXH1633 seem to have a different rating to the ones you listed. Strange, but I'm not complaining about greater low temp friction vs stock.

Different huh? You must have a set that is 'updated', new batch, older or something, it's still a win. Hope you enjoy the pads. Leave your feedback in this thread!