Perform the following steps to inspect the rotor thickness variation:

1. Use a micrometer calibrated in ten-thousandths of an inch to measure the thickness of the brake rotor at four or more points around the rotor circumference at the same distance from the edge of the rotor.
2. A rotor that varies by more than 0.013 mm (0.0005 in) can cause brake pedal pulsation and/or vibration during brake applications.
3. A rotor that does not meet these specifications should be refinished to specifications or replaced.