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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.