Tools Required

Caution: Refer to Brake Dust Caution in the Preface section.

1. The disc brake rotors do not require refinishing as part of routine brake system service. Do not refinish disc brake rotors in an attempt to correct the following conditions:

•	Brake system noise - squeal, growl, groan

•	Uneven and/or premature disc brake pad wear

•	Superficial or cosmetic corrosion/rust of the disc brake rotor surface

•	Scoring of the disc brake rotor surface less than the maximum allowable specification

2. Disc brake rotors should only be refinished if the following conditions exist:

•	Excessive corrosion/rust and/or pitting

•	Cracks and/or heat spots

•	Excessive blueing discoloration

•	Scoring of the disc brake rotor surface in excess of the maximum allowable specification

•	Lateral runout in excess of the maximum allowable specification

•	Thickness variation in excess of the maximum allowable specification

3. Inspect each of the disc brake rotors and determine if the rotors can be refinished and remain above the minimum allowable thickness after refinish specification:

3.1.	Inspect the thickness of each of the disc brake rotors. Refer to Brake Rotor Thickness Measurement

3.2.	Inspect each of the disc brake rotors for excessive surface wear and/or lateral runout. Refer to Brake Rotor Surface and Wear Inspection .

4. If the rotors can be refinished, proceed with the rotor refinishing procedure.

Important: Failure to clean the corrosion from the wheel bearing flange, brake rotor mating surface, and brake rotor mounting face may result in increased lateral runout of the brake rotor and brake system pulsation.

5. Use the J 41013 in order to thoroughly clean any corrosion from the wheel bearing flange.
6. Use the J 42450-A in order to thoroughly clean any corrosion/rust from the brake rotor mating surface and mounting face.
7. Mount the brake rotor to the brake lathe according to the lathe manufacturer's instructions, ensuring that all mounting attachments and adapters are clean and free of debris.
8. Ensure that any vibration dampening attachments are securely in place.
9. With the brake lathe running, slowly bring in the cutting tools until they just contact the brake rotor friction surfaces.
10. Observe the witness mark on the brake rotor. If the witness mark extends approximately three-quarters or more of the way around the brake rotor surface on each side, the brake rotor is properly mounted to the lathe.
11. If the witness mark does not extend three-quarters or more of the way around the brake rotor, re-mount the rotor to the lathe.
12. Following the brake lathe manufacturer's instructions, refinish the brake rotor.
13. After each successive cut, inspect the brake rotor thickness. Refer to Brake Rotor Thickness Measurement .
14. If at any time the brake rotor exceeds the minimum allowable thickness after refinish specification, the brake rotor must be replaced.
15. After refinishing the brake rotor, use the following procedure in order to obtain the desired non-directional finish:

15.1.

Follow the brake lathe manufacturer's recommended speed setting for applying a non-directional finish

15.2.

Using moderate pressure, apply the non-directional finish:

•	If the lathe is equipped with a non-directional finishing tool, apply the finish with 120 grit aluminum oxide sandpaper

•	If the lathe is not equipped with a non-directional finishing tool, apply the finish with a sanding block and 150 grit aluminum oxide sandpaper

15.3.

After applying a non-directional finish, clean each friction surface of the brake rotor with denatured alcohol or an equivalent brake cleaner

16. Remove the brake rotor from the brake lathe.