Brake Rotor Surface & Wear Inspection

WARNING: This page is about a different car, the 2003 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Special Tool Required: Dial Indicator (J-8001), or equivalent.

If the inboard friction surface of the brake rotor is not accessible, reposition and support the caliper with the brake pads. Clean the braking (friction) surfaces of the brake rotor with denatured alcohol or an equivalent approved brake cleaner.
Inspect the braking surfaces of the brake rotor for the following braking surface conditions:
- Heavy rust and/or pitting.
- Light surface rust can be removed with an abrasive disc; heavy surface rust and/or pitting must be removed by refinishing the rotor.
- Cracks and/or heat spots.
- Excessive blueing discoloration.
If the braking surfaces of the brake rotor exhibits one or more of the Braking Surface Conditions, the rotor requires refinishing or replacement.
Using a micrometer calibrated in ten-thousands of an inch, measure and record the thickness variation of the brake rotor at 4 or more points, around the rotor. Ensure that the measurements are only taken within the brake pad lining contact area and that the micrometer is positioned the same distance from the outside edge of the rotor for each measurement.
Using the micrometer, measure and record any grooves present on the rotor braking surface.
Compare the groove (scoring) depth recorded to the brake specifications. See DISC BRAKE SPECIFICATIONS .
If the brake rotor scoring depth exceeds the specification, or if an excessive amount of scoring is present, the rotor requires refinishing or replacement.