I just replaced my front rotors and pads about 5 months ago, and now my rotors are warped b/c of pulsating braking from 40 to 0. I was just wondering do I have to change my pads again, too?

Thanks
James

 

Do you half to? If there is a enough pad NO, WOULD I?
YES! I would replace them because they are now worn into the rotors and the surface of the pad is most likely un even. it's up to you! but I WOULD replace them.

-Rick

 

There's been a lot of threads on this topic - Here's the one that says it all http://forums.corvetteforum.com/zerothread?id=441930
:thumbs:

 

I truly doubt that your rotors are warped. Try doing a real pad break in as mentioned in the following article. GM has big rotors and fairly high temp pads. They need to be bedded and driven fairly agressively to keep from having pad deposit build up. I've seen too many warped rotors cured at a track day.
http://www.stoptech.com/whitepapers/...otors_myth.htm

 

The only accurate way to determine warp is to use a dial run out gauge. They are not that expensive or hard to use and will give you a true indication of warpage or just needing to seat the pads and rotors. Find out the problem before you throw parts at it.

 

Thanks guys, I will try what you all suggested and hopefully it will be inexpensive.

Thanks
James

 

I have yet to own a GM car that hasn't had warped rotors within 30,000 miles. The Vette is no exception (for me). I always torque my lugs to spec with a hand torque wrench and have even tried some of the "pad break in" methods out there. Nothing seems to help. Maybe it's just me.

I recently replaced all four rotors and all pads with these:
http://www.ecklers.com/product.asp?p...AG3A7KATA20CG5 http://www.ecklers.com/product.asp?p...AG3A7KATA20CG5

We'll see if they are any better.

Mike

 

True, but not while mounted to the car. What you think is a warped rotor, while the rotor is mounted to the car, could be lateral runout of rotor/hub assembly. The most accurate way to checked for warped rotors is with a dial indicator with the rotor mounted to a brake lathe. That way, you are measuring the actual rotor, and not a combination of rotor and hub runout.
If you have lateral runout, they make shims to install between the rotor and the hub, up to a maximum spec. After that, the only way to correct lateral runout is with a on-vehicle brake lathe, or replacement.

 

Even that can be a little deceptive. If you have pad build up and compensate for the pad buildup. You could be back to some runout if the pad buldup gets erased with some agressive driving. Again, I have never seen a set or "warped" rotors that doesn't go away with some agressive roadcourse driving. Also don't know of any roadcourse drivers who have "warped" rotors.

 

Wow, mchaney, that is discouraging. Since I started hand torquing the lugnuts myself after each wheel install five Corvettes ago, no rotor warpage here.....Maybe it's just me.

Ranger

 

Not if you check both sides of the rotor, and the high-spot on one side, is the low spot on the other side. However, I agree, most of what people think is warped rotors is caused by pad buildup, and to be truthful, I have never seen a warped "high-performance" rotor. However, I have seen quite a few warped rotors in the low-end class such as Cavaliers, Sunfires, Saturns, etc.
Then again, I just installed sportbrakes, and I have one horrible pulsation. So bad, that this morning I removed all the calipers, made sure the rotors were completely clean, and reinstalled the calipers and wheels.
As for torquing the wheels (before anyone comments), I do a four-stage process. First, I tighten while the wheel is off the ground as tight as I can before the wheel spins. I then hold the tire/wheel assembly, and torque to 50 ft-lbs, then lower and torque to 75, the 100. I always start with the lowest nut, and go in a star-pattern.
Tomorrow (if the weather cooperates) I will replace the two-front sportbrake rotors with the factory original (no pulsation). If the pulsation goes away, then the rotors will go onto a brake lathe and the dial gage will emerge from the back shelf. If that does not solve the problem, the next day it will be the back.
If the rotors are good, I then check for lateral runout, but you can't do a check for LRO until it is verified that the rotor is ok.
If I find a "warped" rotor, it will be returned to sportbrake.
Another thing that is quite common, but hard to diagnose is off center rotors. Most rotors are designed to fit snuggly on the center hub. If the machining on the rotor is slightly off, they will not be center. Most manufacturers do not use the lug studs for centering of the rotors; I'm not sure about Corvette. However, I can attest to another carline that used the center for centering, and wow, did they have problems. Wrapping shim material around the center hub, then installing the brake rotor, cured the problem. Once that was red-Xed, the supplier was called in to prove the problem, and they in turn, went back to reset their machines.