If anything, the PADS are the single most important thing to preventing warped rotors. Coming from a racing background, there are a TREMENDOUS number of different pad compounds out there that have different heat ranges and coefficients of friction. Purchasing cheap 'lifetime' pads is not a good idea because they tend to be hard and eat rotors, thereby making them thinner and leaving a ridge on them. Better quality pads (as far as stopping characteristics go, which is all I care about when it comes to brakes) tend to dust a lot. A byproduct of this is that the heat transfer tends to be less from the pad to the rotor, as the heated pad material is discarded.
Now, as for the term 'warped rotors'.... It is **VERY** uncommon for a rotor to be warped in the sense that it is not truly straight. Most of the time the sensation of 'pulsating' or 'surging' that is felt when applying the brakes is due to pad deposits on the rotor that have been literally baked onto the rotor's surface. Driving style is the single largest cause of this. If you come off of a highway at 70mph, coast for a little bit, then stand on the brakes from 60 to a dead stop for that stoplight at the end of the exit ramp, then stay in that one spot with the EXTREMELY hot pad sitting in one spot on the rotor, you are going to end up depositing pad material on the rotor, which in turn is going to get baked to that one spot. This changes the friction characteristics of that one spot on the rotor, which leads to an uneven amount of friction around the entire surface of that rotor where the pads are pressed against it.
I use the brakes hard, and am cogniscent of the fact that after a hard run or utilizing the brakes from high speed, there will be a tremendous amount of heat built up in the rotors. The simplest solution to this problem is to stop short of where you need to be. I'm not talking about leaving 3 carlengths by any means, but if you stop about 10 feet short of where you need to be, you can VERY slowly creep forward (easy in an automatic) a little bit at a time to keep the hot pads moving around to a different spot on the rotor. This prevents that depositing and 'baking' I explained above. The other option is that if you are not on an incline, shift into neutral and just completely take your foot off of the brake pedal so that the pads once again aren't pressed hard against the rotor surface. If you are lucky, the vehicle will roll slightly forward or backward slowly and will accomplish the same thing as above when I said to creep forward.
By following these guidelines, I have not had a warped rotor in SEVERAL years in any of my vehicles, despite my hard braking tendencies. I've even braked quite hard and come to abrupt stops while towing in my Blazer and have had no problems with rotors warping on that vehicle. Like I said, a lot has to do with knowing your vehicle and being in touch with every aspect of it. I think having more of an engineering based background, I can understand these concepts a bit easier than the average driver on the road, but I stay very in touch with what my vehicles communicate back to me and adjust according so as to make the situation a little 'easier' on the vehicle as much as possible.
Just some things to think about.
Ricky
greasefingers said:
My rotors are just starting to warp. I can feel them shudder, only under hard braking. Otherwise they feel fine. I am going to have them cut at the local auto store and throw on front pads. I never use new pads without having the rotors cut or replacing all together. There is nothing special about brake pads so I will find anyone other than the dealer for these.
I will be very interested to see if the rotors are solid cast iron. This is the cause of many warped rotors. I have a jeep and the rotors have to be replaced every 20 to 30k miles. They use a composite rotor. Cast iron as a core and some other steel on either side. Solid rotors are the same thickness throughout. Composites are stepped and have two different thickness
