Brake Rotor Thickness Variation Measurement
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 inch) 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.