Okay, I did a search to see if this was covered before, and I found mixed opinions. So I'm throwing in my own experience.

A long while back I read an article that said that "warped rotors" are just brake pad material unevenly deposited onto the rotor surface when it is hot and not turning. The author mentioned he had never seen a rotor that really was warped (though they might exist). He also noted that, given that new rotors aren't much more money than turning and that turning reduces rotor thickness, it was better to replace rotors if anything.

Since then, whenever possible after a hard stop I would let off the brakes. After a drive with lots of hard stopping, I would wait a minute before applying the e-brake. Before my brakes would vibrate quite noticeably, then after several months it completely disappeared. The change was gradual and I don't know exactly how long it took.

Hope that helps somebody.

 

That Stoptech article has got some great info in it. I've also solved the "warped rotor" issue on a couple of cars since reading that.


.

 

Yup... that's one of the first rules when you go to the track; Don't put the e-brake on after you come off the track (or sit with brakes applied). The hot brakes will transfer pad material.

 

Another potential solution is to sand the rotor faces to remove the transfer layer. Never tried it myself, but it'd be worth a shot.

 

ive done this on rx7's too.

having turned a few rotors on a brake lathe, i have seen warped ones.

and some newer cars like subaru, have rotors with a hardening on them, so you're not supposed to turn them, because it takes the hardening off

 

Warped rotors are rare but can happen. It happened to me. When I took the rotors off you could place them on a perfectly flat surface and they would wobble just like a chair with a short leg. I took them to be turned and the shop said they were so bad that there was a chance of their machine breaking so refused the service.

Replacing them solved that problem but I still had a pulsation under breaking. What I found was the wheel bearing on one wheel was bad. After replacing that I now have perfect brakes again.