Brake Rotor Thickness Variation Measurement
Inspect the thickness variation by measuring the rotor thickness at 4 or more points around the circumference of the rotor. Use a micrometer that is calibrated in increments of 0.025 mm (0.001 inch). Perform 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) may cause a pedal pulsation and/or a front end vibration during the brake applications. A rotor that does not meet these specifications should be refinished to the specifications or replaced.