Brake Analysis Help

[Voice of Reason]

The brakes on my TA are acting strange so I'm looking for input from those with brake experience. I'm pretty novice with brakes so any advice I'm interested in.

The issue started last fall and now that I've taken it out again this year I still have it. The brakes don't act like they're warped but instead seem like they have excessive material transfer from the pads if that's even possible. Braking from 60 with regular pressure is causing a consistent whirring noise, like the pad is dragging on material that stuck to the rotor. I just tried bedding them again and since have not tried any normal stopping, but the brakes look like the pics below which is pretty much what they looked like before. This is at about 8,200 miles with 3 road courses and 5 auto x on them.




Both fronts look like this and the rears are completely clean. I haven't taken the pads out but can see that they are still plenty thick.

Could the front pads be shot? I'm thinking I should change them, but to what I'm not sure. And if I do should I change the rears as well? Anything else?

Thanks.

[Rapidrezults]

I had this EXACT problem with my TA. I went crazy trying to figure it out, it was so loud when stopping. I didn't think I'd ever read another post describing this, I just thought it was from the tortureous use they got from some Laguna Seca track days. Anyway, i tried everything, I sanded all rotors front and back, replaced pads etc. Finally the dealer replaced my front rotors and pads under warranty (and put them on backwards while doing it) and the problem went away. I sold the car shortly after.

I had it pinpointed to a specific MPH where the noise would start, and gradually get louder as you slowed down. To the point where people riding passenger would ask if my brakes were okay. Lol. It seemed to only start at MPH I believe above 40+ if I recall correctly. Good luck, and I tried a bunch of stuff. If you want any more specifics as to exactly what I tried PM me.

[Andi]

I think the issue is the TA pad doesn't do too well when overheated... And then when it cools off it isn't abrasive enough to clean off the pad deposits. When I bought my car I swore the previous owner must have destroyed the F rotors as it had a bad vibration when applying the brakes at highway speeds. 1,000 miles and one track day later it never got any better. I even tried sanding down the rotors and it only got marginally better.

Then I bought a set of Raybestos ST47 race pads from porterfield (pad shape d1001-18 for the TA). I took the car out last Saturday to bed in the new pads and within half an hour 80% of my vibration was gone. I'm cautiously optimistic that the better pads will solve the problem moving forward.

I have a feeling the stock TA pads are adequate for street use, or for a motor trend 3 lap test, but not even close for 20 minute sessions. At least not the fronts.

I'm going to leave the rears stock for now and see how the brake bias feels.

[Voice of Reason]

Interesting that this seems to be a common problem for at least a few of us with the TA brakes. Temps get back to the 50s and 60s today and tomorrow, I'm going to spend some time trying to bed the stock pads again to see if that can clean them up. I have no issues replacing the pads but sanding them will be a last resort after my dealer telling me there's nothing they can do warranty wise. IF it comes to that I've read you should use garnet paper when sanding brake rotors, is that what you both tried using? What about using a flex hone like pictured below, I've seen at least one site mention using one of these.

[ACR Steve]

Looks like a heat issue once there bed you cant re bed. I would inspect the pads I think you will find they are cooked.

[Voice of Reason]

Looks like a heat issue once there bed you cant re bed. I would inspect the pads I think you will find they are cooked.

Good to know. So in your opinion will new pads and bedding them correctly the first time clear this up? Anything I should do to prep the rotors like sanding before installing new pads? And where is the best place to buy pads, Jon B?

[ACR Steve]

Yes if they are not grooved badly I would lightly sand them. (If really grooved they need to be professionally done or replaced) If the rotor isn't that badly grooved and you just replace the pads then yes go through the bed in process that the pad manufacturer recommends. I am very sure your pads are shot. That's a lot of mileage which includes Auto-X and track days for a stock pad . That was probably part of the problem . If you use the wear notch on the pad you need to through them out at about the 3/4 mark. They will overheat to fast because not enough material on them. This was probably what caused most of the issues. Everyone always waits to long before replacing. On my race car I get rid of them at about 50-60% wear

First though inspect the pads if they looked burnt, discolored or cracked then heat was your issue. Probably because they are a stock pad made for the street and not tracking or Auto-x and compounded by wearing them down 3/4 or probably more

New pads - Jon B is great...... I would also ask him about adding the ACR duct . You need to get more air on those brakes. Also good idea to upgrade your brake fluid

[Voice of Reason]

I just felt them again (working from home has benefits) and they aren't grooved badly at all so I'll go with a light sanding. I installed the ACR ducts last week thinking heat was a factor and I'll give Jon a call for new pads. Brake fluid was already on my list to replace before my first track event this year so I'll be sure that gets done.

Thanks!

[JonB ~ PartsRack]

Thanks Steve...

definitely a pad / glaze issue. The ducts can help prevent pad overheating, and we have ducts and pad options in stocks, as well as spare rotors. JonB@PartsRack.com

[Andi]

I just felt them again (working from home has benefits) and they aren't grooved badly at all so I'll go with a light sanding. I installed the ACR ducts last week thinking heat was a factor and I'll give Jon a call for new pads. Brake fluid was already on my list to replace before my first track event this year so I'll be sure that gets done.

Thanks!

Bedding in a set of aggressive race pads will give you an order of magnitude more "effective sanding" than doing it the hard way. I learned this the hard way.. Just saying.

[Voice of Reason]

UPDATE

I've solved 95% of the issue and I can live with the occasional and minor 5% that remains. I'm posting my solution so the next person who experiences this can search and find this post.

Before doing anything myself I took the car to my dealer to look over. They said the rotors did overheat and they recommended replacing both front rotors and pads for $3,000. I didn't care to drop 3k without at least trying my own fixes so I passed on their offer. They did attempt to clean the rotors themselves and this is what it looked like:


Yeah, not that great of a job.

I decided I was going to work the rotors over myself and try new pads. So I ordered CarboTech XP20/XP8 from Mark and set to work sanding the rotors with the flex hone I posted a pic of above.

When I took the stock pads off I notice they're all cracked, I must be hell on brakes!


Here are my finished sanded rotors:

10 minutes on each rotor face (so 20 min per rotor) and I have them looking as new as I can get. There is almost no grooving on the rotors so I'm hopeful this will do it. There were also no cracks on the rotors at all.


Before installing the pads I do a quick comparison and my 8,800 mile stock pads are still just as thick as the brand new pads. I thought that was interesting despite them having some racing days on them.

I install the pads to take for a drive and immediately on my first braking from 55-40 the groaning/moaning is still there and LOUD. I decided to go ahead with re-bedding them anyway and go through the procedure. While doing so the noise lessens probably 75%. I limp home without touching the brakes again and let it cool 24 hours.

The rotors now look like this with a nice even pad transfer.


Today I took the car for a quick drive and the noise from 55-40 is virtually gone! Letting the pads and rotors cool overnight took the noise reduction from 75% yesterday to 95% today. If I wasn't super tuned in to listening for it now there's no way I would ever notice it.

So I'm considering this done for now and will keep a close watch during and after road course days to ensure it doesn't return. And if it does I'll be buying rotor rings from JonB, there's no way I'm getting full replacements from my dealer for what Dodge is charging for them.

[lmcgrew79]

I can send you a pair of used up dtc70 hawk racing pads, put them on go do a few hard stops and but your stock ones back. It will clean them up.

[swexlin]

Good stuff, thank you. And yes, Jon B is much better pricing.

[Rapidrezults]

Glad to hear that you have had some success with sanding. You did an amazing job sanding them! One thing to note is when I got done sanding mine for the second(or third -can't remember) time, I thought the problem was mostly solved, until I started driving more and heating them up and then magically the sound came back. There would be the occasional day I would take it out and the sound was minimal. As I've mentioned to you, this problem drove me nuts! I didn't however sand them to the degree that you did, so I hope your fix is a more permanent one.

[Voice of Reason]

Glad to hear that you have had some success with sanding. You did an amazing job sanding them! One thing to note is when I got done sanding mine for the second(or third -can't remember) time, I thought the problem was mostly solved, until I started driving more and heating them up and then magically the sound came back. There would be the occasional day I would take it out and the sound was minimal. As I've mentioned to you, this problem drove me nuts! I didn't however sand them to the degree that you did, so I hope your fix is a more permanent one.

You aren't kidding about the noise, it became like nails on a chalkboard for me. I decided I wasn't worried about sanding too much or causing an uneven surface myself because there's no way I could make them worse.

Side note - The new XP20 pads in front do squeak a bit coming up to a stop. But I find it livable, especially if they will hold up better at the track.

[FrgMstr]

I have used this 3M rotor kit in the past for removing pad material from my rotors when overheating has happened. Works very well, and does not seem to be as abrasive as the solution above.

3M 01410 Roloc Brake Rotor Surface Conditioning Disc Starter Pack

[AZTVR]

I have used this 3M rotor kit in the past for removing pad material from my rotors when overheating has happened. Works very well, and does not seem to be as abrasive as the solution above.

3M 01410 Roloc Brake Rotor Surface Conditioning Disc Starter Pack

That kit is 120 grit. The flex hone pictured can be purchased as 60, 120, or 240 grit.

[Voice of Reason]

I bought the 120 and 240 flex hones and only used the 120. I decided going to the 240 may polish them too much if that's even possible.

[nuviper]

I can send you a pair of used up dtc70 hawk racing pads, put them on go do a few hard stops and but your stock ones back. It will clean them up.

Hi Imcgrew 79,

Did you mean that using racing pads can clean the rotors glazed by the stock pads? I had a track day last Saturday and my front rotors are full of this now. Dealer told me to change the front rotors, but I want to do some work myself before spending the money.

Thanks!
nuviperIMG_8907.jpgIMG_8908.jpgIMG_8909.jpg

[Voice of Reason]

It's likely that aggressive pads alone would have solved my issue, after track days now they do a good job of cleaning the rotors themselves during normal driving. My moan sound is now completely gone. However! These pads do squeal when coming to a stop. it's mildly annoy but nothing even close to as bad as the moaning from before.

[nuviper]

It's likely that aggressive pads alone would have solved my issue, after track days now they do a good job of cleaning the rotors themselves during normal driving. My moan sound is now completely gone. However! These pads do squeal when coming to a stop. it's mildly annoy but nothing even close to as bad as the moaning from before.

That sounds great! Then I plan to put some carbontech pads on. Did you do any other mods like braking fluid and the braking lining?

[darbgnik]

I can send you a pair of used up dtc70 hawk racing pads, put them on go do a few hard stops and but your stock ones back. It will clean them up.

Knew this sounded familiar! From Stoptech website:

Uneven pad deposits can often be effectively removed from rotors by using a pad compound that is more abrasive at lower temperatures. StopTech has found the Hawk 9012 (Hawk Blue) compound to be particularly effective in removing uneven pad deposits from rotors. Other higher temperature performance pads may also effectively “scrub” off uneven pad deposits, however we have found the Hawk 9012 to be the best for this application

[Voice of Reason]

That sounds great! Then I plan to put some carbontech pads on. Did you do any other mods like braking fluid and the braking lining?

I did change to a higher temp fluid (can't remember which one).

Something else to check is the caliper piston dust shields. The new pads worked so well this summer while racing that I melted my dust shields.

[nuviper]

Thanks for your information darbgnik!

[nuviper]

I did change to a higher temp fluid (can't remember which one).

Something else to check is the caliper piston dust shields. The new pads worked so well this summer while racing that I melted my dust shields.

Thanks man. I think I can first try the pads this time.