Warped Rotors A Myth?
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From: Fitchburg Ma _ToastedRice_
funny, i think i said something similar to this (not as in depth) in the ever so controversial slotted rotors thred...
MYTH # 3 - A SOFT BRAKE PEDAL IS THE RESULT OF PAD FADE
The all too familiar mushy brake pedal is caused by overheated brake fluid, not overheated pads. Repeated heavy use of the brakes may lead to "brake fade". There are two distinct varieties of brake fade
A) When the temperature at the interface between the pad and the rotor exceeds the thermal capacity of the pad, the pad loses friction capability due largely to out gassing of the binding agents in the pad compound. The brake pedal remains firm and solid but the car will not stop. The first indication is a distinctive and unpleasant smell which should serve as a warning to back off,
B) When the fluid boils in the calipers air bubbles are formed. Since air is compressible, the brake pedal becomes soft and "mushy" and pedal travel increases. You can probably still stop the car by pumping the pedal but efficient modulation is gone. This is a gradual process with lots of warning.
The all too familiar mushy brake pedal is caused by overheated brake fluid, not overheated pads. Repeated heavy use of the brakes may lead to "brake fade". There are two distinct varieties of brake fade
A) When the temperature at the interface between the pad and the rotor exceeds the thermal capacity of the pad, the pad loses friction capability due largely to out gassing of the binding agents in the pad compound. The brake pedal remains firm and solid but the car will not stop. The first indication is a distinctive and unpleasant smell which should serve as a warning to back off,
B) When the fluid boils in the calipers air bubbles are formed. Since air is compressible, the brake pedal becomes soft and "mushy" and pedal travel increases. You can probably still stop the car by pumping the pedal but efficient modulation is gone. This is a gradual process with lots of warning.
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From: Motor City(ish)
LakevilleSSEi,
I will post a pic tomorrow taken by our evaluation group showing severe transer of pad material to the rotor. It'* just a plain rotor, that was taken off of a customer'* car. It'* not cross-drilled or slotted. The customer was complaining of a brake pulsation. I was pretty shocked to see this myself....
This very subject of warped rotors has become quite a hot topic between our warranty group and product support group lately. I'm going to gather some more info and I'll post back.
I will post a pic tomorrow taken by our evaluation group showing severe transer of pad material to the rotor. It'* just a plain rotor, that was taken off of a customer'* car. It'* not cross-drilled or slotted. The customer was complaining of a brake pulsation. I was pretty shocked to see this myself....
This very subject of warped rotors has become quite a hot topic between our warranty group and product support group lately. I'm going to gather some more info and I'll post back.
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From: Fitchburg Ma _ToastedRice_
Originally Posted by BonneMeMN
Brake fade can also be caused by pads becoming glazed over from heat.
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From: Bedroom, Ontario
I guess if the theory is correct.. didn't read the whole thing.. hooked on phonics never taught to read that much 
So that mean if you run the car with one end lifted up and in drive. the rotor will spin on teh lose one with tires off.. put like 1000 Sandpaper grit on it to buff out the so called residue and voila.. cured ??? Guess someone will have to find some time to try it
NEVER MIND !!!
Finally read the ending.. skipped to it..
So that mean if you run the car with one end lifted up and in drive. the rotor will spin on teh lose one with tires off.. put like 1000 Sandpaper grit on it to buff out the so called residue and voila.. cured ??? Guess someone will have to find some time to try it
NEVER MIND !!!
Finally read the ending.. skipped to it..
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From: Farmington, Minnesota =MWBF '05 SURVIVOR= =CEBF '06 SURVIVOR= =August '06 COTM=
Originally Posted by Drifter420
I guess if the theory is correct.. didn't read the whole thing.. hooked on phonics never taught to read that much
So that mean if you run the car with one end lifted up and in drive. the rotor will spin on teh lose one with tires off.. put like 1000 Sandpaper grit on it to buff out the so called residue and voila.. cured ??? Guess someone will have to find some time to try it
NEVER MIND !!!
Finally read the ending.. skipped to it..
So that mean if you run the car with one end lifted up and in drive. the rotor will spin on teh lose one with tires off.. put like 1000 Sandpaper grit on it to buff out the so called residue and voila.. cured ??? Guess someone will have to find some time to try it
NEVER MIND !!!
Finally read the ending.. skipped to it..
Anyways...ya post that info and pics. Like I said, that sounds really odd to me that can happen on something that'* constantly in friction with the pad.
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Originally Posted by toastedoats
Originally Posted by BonneMeMN
Brake fade can also be caused by pads becoming glazed over from heat.
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GM ROTORS WARP! It is simply a fact of life, deal with it.
The stock GM rotors are as cheaply made as GM can get away with without violating safety laws, they are smaller on average than other cars in their class and they certainly do warp.
Having used ceramic pads with standard rotors I can say the it is certainly not attributable in all(or most) cases to "material transfer".
The only solution to the problem is not to buy your replacement rotors from GM. Brembo makes an excellent OEM replacement for just about every GM car out there. PowerStop also is extremely resistant to warping in my experience( I beat the hell out of mine and never had any trouble with them), and StopTech and many other companies produce rotors that don't warp under the stress of everyday driving.
The stock GM rotors are as cheaply made as GM can get away with without violating safety laws, they are smaller on average than other cars in their class and they certainly do warp.
Having used ceramic pads with standard rotors I can say the it is certainly not attributable in all(or most) cases to "material transfer".
The only solution to the problem is not to buy your replacement rotors from GM. Brembo makes an excellent OEM replacement for just about every GM car out there. PowerStop also is extremely resistant to warping in my experience( I beat the hell out of mine and never had any trouble with them), and StopTech and many other companies produce rotors that don't warp under the stress of everyday driving.
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