You recently (8/29) recommended Nathan slow down on descending mountains to not warp his brake rotors. However, you forgot that he drove the car 36,000 miles without problems but now has to turn the rotors every 4k Miles. This doesn’t make sense! I have the same problem with a 96 Olds 88 LSS. I drove the car problem free for nearly 40k miles, but then after the rotors warped and I replaced them, like Nathan I have to turn the rotors or replace them every 3 to 4k miles. I think there is a fundamental problem with the caliper design. I’ve tried five different brands of brake pads, including high-performance pads, different brands of rotors including OEM. I think the calipers themselves have warped from not being correctly heat-treated or stress relieved and the calipers are crooked, causing the rotors to warp. I recommend you recontact Nathan and revisit this question. BTW, great show and I try to outwit you every show - usually with great success! All the best and Semper fidelis! David Kiffer, Colonel, U.S. Marines
You could have sticky calipers. Have the caliper bolts been lubed with brake grease? Have the calipers been replaced? Rotors should not warp in 3k to 4k miles.
Lots of things can create break warping. Sticky calipers can do it. Getting them real hot and going through a deep puddle can also do it. If Nathan is having warping problems he should consider getting cryogenically treated rotors. They are very resistant to warping and also to wear. Treated rotors are being used by many police units to cut the cost of trying to stop a heavy Crown Vic loaded with police equipment and a full shift’s supply of doughnuts and coffee from some very high speeds.
What are you replacing the rotors with???
Pay extra money and buy the OEM rotors…I’ve seen some real thin and junky rotors out there.
I’ve seen OEM rotors that are just as crappy as any discount rotor.
I buy Brembos myself.
There are a number of possibilities for your troubles, not necessarily a design issue.
The caliper piston has a rubber seal around its circumference. This seal rocks slightly in the bore as the piston is forced outward. The elastic tension created by the seal twisting is responsible for slightly retracting the piston as the brake is released and pressure is removed. Over time, like all rubber materials, the seal hardens and loses some of its elasticity. In addition, crud builds up in the piston bore and can impede the piston from travelling smoothly in the bore. The result is slight dragging of the pads=faster wear.
The calipers must be serviced at the brake pad interval. Sliding calipers must be free to move as the pads wear or stress is placed on the caliper housing.
The flexible hose connecting the caliper to the hard brake line can break down internally and create a restriction for fluid to return from the caliper. Another potential cause of brake drag.
Worn bearings can allow rotor tilt and more rubbing than brand new, tight bearings.
New pads and rotors should be bedded in. When people buy a new car, they often treat it differently than a well used one. The brakes may have been treated differently when new compared to the subsequent repairs 40k miles later.
Once your rotors warp, and Nathan said he continued to use the same rotors, only had them re-surfaced, not replaced, they tend to warp again sooner than they did the first time. If I ever had warped rotors, I would not have them re-surfaced, I would have them replaced, with OEM or better (treated for heavy use conditions if need be).