The Mustang Forum for Track & Racing Enthusiasts

Taking your Mustang to an open track/HPDE event for the first time? Do you race competitively? This forum is for you! Log in to remove most ads.

  • Welcome to the Ford Mustang forum built for owners of the Mustang GT350, BOSS 302, GT500, and all other S550, S197, SN95, Fox Body and older Mustangs set up for open track days, road racing, and/or autocross. Join our forum, interact with others, share your build, and help us strengthen this community!

Excessive Chatter and Heat marks on rear rotors

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

ufnavy06

Some say he has a tattoo of his face on his face.
So I'm getting my RSLs put on my front rotors today and the mechanic calls me up to say I have "excessive chatter and heat marks on the rear rotors, so we're going to recommend replacing them." I only have 15,808 miles on the car so I'm trying to ascertain the cause. I haven't felt anything out of the ordinary but I'm sure that has to do with the brake bias. Thoughts and or recommendations?

A bit of a damper to go to MRLS on Friday and be worried about brakes, not to mention I need to bed these new pads.
 

TMSBOSS

Spending my pension on car parts and track fees.
7,530
5,247
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
ufnavy06 said:
So I'm getting my RSLs put on my front rotors today and the mechanic calls me up to say I have "excessive chatter and heat marks on the rear rotors, so we're going to recommend replacing them." I only have 15,808 miles on the car so I'm trying to ascertain the cause. I haven't felt anything out of the ordinary but I'm sure that has to do with the brake bias. Thoughts and or recommendations?

A bit of a damper to go to MRLS on Friday and be worried about brakes, not to mention I need to bed these new pads.

Same for me. Measured the front pads and have over 70% pad life remaining. Rears needed new pads and rotor rings. WTF?? Bought and installed fronts and rears together.

I believe this is related to traction control. I ran a few sessions with TC on. I also like running the Ramps at the interstate near the limit. I have not turned TC off for highway driving. I will now.

At least I am replacing the "Cheaper" set.

All set for VIR on Friday.

Good luck with MRLS!!! ;D
 

ufnavy06

Some say he has a tattoo of his face on his face.
Thanks. So using the search function, it seems it's the TC/advanced track system kicking in while I'm on the track. I haven't felt confident enough to take the nannies off, but I suppose I should and drive closer to 6/10ths.
 
1,022
99
Exp. Type
HPDE
Exp. Level
10-20 Years
Texas
As long as there is no vibration in the brake pedal and brake application is smooth don't worry about the rear rotors. I believe I know what your mechanic is referring to and it's just pad transfer. I have seen the same thing on my car in the past.

Another subject to bring up is stability control aka "advanced track". When I drove the car with the nannies on I would go through rear pads as fast as I did fronts. I also went through axle seals and bearings due to the excessive heat transferred from the brakes through the rear axle because of advanced track. What you don't realize is when you leave all that stuff on at the track it is constantly working to keep you from getting into an oversteer or understeer situation. Once I turned everything off I stopped replacing axle seals as often and my rear pads last three times as long as my fronts do. If you are still driving with all the nannies on that is fine but realize you will wear through rear pads, rotors, bearings, and axle seals faster.

Adam
 
I agree with Adam, it's normal. Don't replace the rotors. We can discuss turning off TC at dinner on Thurs.
 

dmichaels

Papa Smurf
547
30
CT
Also agree replacing the rear rotors is not necessary. I replace mine only when they crack (start to crack that is) or have noticeable wear.

But TC will burn up pads and such quickly. Then again it's a nice safety net
 
To someone that doesn't know how mustangs TC works, the pad transfer on the rotor would look unusual, so can't blame your mechanic for letting you know about it.

I get the same thing from driving on the street. Sometimes it clears out after a track weekend (with nannies off, aka the b!tch switch ;D)
 

TMSBOSS

Spending my pension on car parts and track fees.
7,530
5,247
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
My ultra low tech solution for this weekend is to make labels for the steering wheel horn button reminding me to turn off nannies, check camera, safety gear and fuel.

They peel right off when finished.

I believe I saw this on Gary's car.

Running at 6/10's won't last long. You have more control without the nannies.

Good luck.
 

TMO Supporting Vendors

Top