- 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 |
- 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 |
- 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:
- If the rotors can be refinished, proceed with the rotor refinishing
procedure.
- Mount the brake rotor to the brake lathe according to the lathe
manufacturer's instructions.
- Ensure that any vibration dampening attachments are securely in
place.
- With the brake lathe running, slowly bring in the cutting tools
until they just contact the brake rotor friction surfaces.
- 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.
- 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.
- Following the brake lathe manufacturer's instructions, refinish
the brake rotor.
- After each successive cut, inspect the brake rotor thickness.
Refer to
Brake Rotor Thickness Measurement
.
- If at any time the brake rotor exceeds the minimum allowable thickness
after refinish specification, the brake rotor must be replaced.
- After refinishing the brake rotor, use the following procedure
in order to obtain the desired non-directional finish:
13.1. | Follow the brake lathe manufacturer's recommended speed setting
for applying a non-directional finish |
13.2. | 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 |
13.3. | After applying a non-directional finish, clean each friction surface
of the brake rotor with denatured alcohol or an equivalent brake cleaner |
- Remove the brake rotor from the brake lathe.