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

A rotor in the front disc brakes that varies in thickness by more than 0.013 mm (0.0005 in) can cause pedal pulsation and/or front end vibration during brake applications. Replace or refinish to specifications any rotor that exceeds the designated thickness variation range.