Description

Important: DO NOT refinish brake rotors when performing routine brake maintenance, such as replacing worn disc brake pads. Refinish a rotor ONLY under the following circumstances:
^ There is a complaint of brake pulsation.
^ There is scoring greater than 1.5 mm (0.060 inch).

All brake rotors have a minimum thickness dimension cast into the rotor. This dimension is not a minimum refinishing dimension. The minimum refinishing dimension is larger than the discard dimension. Do not use a brake rotor that, after refinishing, will not meet the minimum thickness shown on the rotor. Replace it with a new rotor. Refer to Component Specifications.

Accurate control of the rotor tolerance is necessary for proper performance of the disc brakes. Machine the rotor using precise equipment. Service machining equipment on a regular basis. Follow the manufacturer's recommended maintenance procedure.

Ensure that the following tool accessories are in good condition when refinishing the rotors:
^ The attaching adapters
^ The tool holders
^ The vibration dampeners
^ The tool bits

Always use sharp cutting tools and bits. Replace cutting bits using equipment recommended by the manufacturer. Dull or worn tools leave a poor surface finish which will affect braking performance. Always use anti-chatter silencer attachments when refinishing braking surfaces. The attachments eliminate tool chatter and will result in a better surface finish. Ensure that the adapters are clean and free of nicks.

In order to correct brake pulsation, refinish the rotors using an on-vehicle brake lathe. Follow the equipment manufacturer's recommended specifications and procedure.

Important: Remove any rust and scale from the rotor and spindle hub mating surfaces. Failure to do so may introduce excessive lateral runout when the rotor is mounted on the brake lathe, or when the rotor is reinstalled on the spindle hub.

The following two procedures are recommended and achieve adequate results using two different off-vehicle disc brake lathes. If any other lathe is used, follow that lathe's instructions and recommendations:





AMMCO BRAKE LATHE





ACCU TURN BRAKE LATHE
1. Locate the deepest score and turn the rotor micrometer knob until the tool bit bottoms out at the deepest point of the score.
2. Zero the scale and back out the tool bit.
3. Advance the cutter handwheel until the bits have cleared the inner edges of the rotor face.
4. Adjust the micrometer knobs for approximately 0.127 mm (0.005 inch) more than the first reading. Use this method in order to resurface the rotor in one cut.