Envoy 4WD V6-4.3L VIN W (1998)
Brake Rotor/Disc: Testing and Inspection
Brake Rotor Thickness Variation Check
Check for thickness variation by measuring the rotor thickness at four or more points around the circumference of the rotor (1-4). Use a micrometer
calibrated in ten-thousandths 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 0.010 mm (0.0003 inch) can cause brake pedal pulsation and/or vehicle vibration during brake applications.
Refinish to specifications or replace a rotor that does not meet these specifications.