Thickness Variation Check

Check 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 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) can cause pedal pulsation and/or front end vibration during brake applications. A rotor that does not meet these specifications should be refinished or replaced.