I bought the car with severely warped front rotors, knowing that I could swap out the rotors and pads in just over an hour. After disassembling everything, I figured out why the rotors warped in the first place. The calipers had a bit of a bow in the sliding surface the pads slide across. So the pads fit nicely in the caliper when first installed, but after 50% of the pad has worn away, only the outer pad can move. The inner pad effectively gets stuck and pressure from the outer pad is all that is slowing the car down. Eventually the rotor bends due to lack of the support by the rear pad (as it wears away) and you get severely warped rotors and severely uneven pad wear.
I bought the car with severely warped front rotors, knowing that I could swap out the rotors and pads in just over an hour. After disassembling everything, I figured out why the rotors warped in the first place. The calipers had a bit of a bow in the sliding surface the pads slide across. So the pads fit nicely in the caliper when first installed, but after 50% of the pad has worn away, only the outer pad can move. The inner pad effectively gets stuck and pressure from the outer pad is all that is slowing the car down. Eventually the rotor bends due to lack of the support by the rear pad (as it wears away) and you get severely warped rotors and severely uneven pad wear.
- David C., Vienna, VA, US