Rick CarltonBrake disc rotors do not warp. Instead, they become irregular due to excessive lateral run out of the rotor face.
This is usually triggered by an uneven plain across the rotor face, which can be caused by deposited brake materials on the rotor face during hard braking and/or excessive heat over time. You can also get build-up on the axle hub, have pad/caliper misalignment, or physical damage to the rotor disc itself. (Learn more about the mechanics of rotors here.)
There are two central ways to fix an out-of-spec rotor: either replace the rotor or re-surface it (a/k/a machine turning). Re-surfacing a rotor makes it smooth so it operates within proper tolerances. It’s also less expensive than buying a new rotor.
The exception is with performance cars. In that case, don’t refurbish your rotors. A complete replacement is the best course.
John Butler
