Brake Rotor Surface and Wear Inspection (With ZL1 (Front))

Brake Rotor Surface and Wear Inspection (With ZL1 (Front))

Warning: Refer to Brake Dust Warning Brake Dust Warning.


Note: Due to the floating design of the brake rotor, the front brake rotor cannot be refinished. If the front brake rotor is found to be above the maximum specification, it must be replaced.

Note: Do not remove the brake rotor from the wheel hub.

1. If the inboard friction surface of the brake rotor is not accessible, reposition and support the brake caliper bracket and/or brake caliper with the brake pads. Refer to Front Brake Rotor Replacement (LFX) Front Brake Rotor ReplacementFront Brake Rotor Replacement (L99, LS3) Front Brake Rotor ReplacementFront Brake Rotor Replacement (LSA) Front Brake Rotor Replacement.

2. Clean the friction surfaces of the brake rotor with denatured alcohol, or an equivalent approved brake cleaner.

3. Inspect the friction 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

4. If the friction surfaces of the brake rotor exhibit one or more of the Braking Surface Conditions, the rotor requires replacement.




5. Using a micrometer calibrated in thousandths-of-a-millimeter, or ten-thousandths-of-an-inch, measure and record the scoring depth of any grooves present on the rotor friction surfaces.

6. Compare the groove scoring depth recorded to the following specification:

Brake rotor maximum allowable scoring: 1.50 mm (0.059 in)

7. If the brake rotor scoring depth exceeds the specification, or if an excessive amount of scoring is present, the rotor requires replacement.