Inspect for thickness variation by measuring the rotor thickness at 4 or more points around the circumference of the rotor. Use a micrometer calibrated in ten-thousandths of an inch. Make all measurements at the same distance in from the edge of the rotor.

A rotor that varies in thickness by more than 0.013 mm (0.0005 in) causes brake pedal pulsation and/or vehicle vibration during the brake application. Refinish to specifications or replace a rotor that does not meet these specifications.