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Brake Rotor Surface and Wear Inspection (J55)




Brake Rotor Surface and Wear Inspection (J55)
Warning: Refer to Brake Dust Warning (Brake Dust Warning).


Note: The brake rotors are coated with a corrosion inhibitor, and must not be refinished.

1. If the inboard friction surface of the brake rotor is not accessible, reposition and support the caliper with the brake pads. Refer to Front Disc Brake Pads Replacement (J55) (Front Disc Brake Pads Replacement (J55))Front Disc Brake Pads Replacement (JL9) (Front Disc Brake Pads Replacement (JL9)) and/or Rear Disc Brake Pads Replacement (JL9) (Rear Disc Brake Pads Replacement (JL9))Rear Disc Brake Pads Replacement (J55) (Rear Disc Brake Pads Replacement (J55)).
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
* Cracks and/or heat spots

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.