Procedures

Brake Disc Machining





CAUTION: Do not use a bench lathe to machine the brake discs. A bench lathe may cause brake disc on-vehicle lateral runout and brake roughness.

NOTE: Read the entire operating manual and/or view the video shipped with the lathe before installing, operating or repairing the lathe.

NOTE: If the thickness of the brake disc is less than the minimum thickness to machine specification, install a new brake disc. This will make sure that the brake disc will be above minimum thickness after machining.

NOTE: Do not machine new brake discs.

NOTE: Lateral runout and disc thickness variation measurements are not required because correct adjustment of the on-vehicle brake lathe will make sure that these dimensions are within specifications.

1. WARNING: Before servicing a vehicle equipped with a fire suppression system, depower the system by following the procedure in Fire Suppression System. Failure to follow the instructions may result in serious personal injury.

NOTE: It is not necessary to disconnect the brake line from the brake caliper.

Position the brake caliper and brake caliper anchor bracket aside
2. Mark the brake disc and the wheel stud for correct indexing during re-assembly.
3. Remove the brake disc from the hub.

4. CAUTION: Do not use an abrasive sanding disc since it will remove paint or other protective finishes from the wheel or metal from the mounting surfaces, adversely affecting corrosion protection and brake disc lateral runout.

Remove corrosion from the wheel mounting surface, both disc mounting surfaces and the hub mounting surface.

5. Align the match marks and install the brake disc on the hub.
6. Machine the brake disc using an on-vehicle brake lathe.
1. Install the hub adapter and silencer belt, if necessary.
2. Install the cutting lathe.
3. If the lathe is not self adjusting, adjust the lathe oscillation using a dial indicator. Total indicated reading (TIR) target is 0.000 mm (0.000 inch), maximum is 0.08 mm (0.003 inch).
4. Center the cutting head, adjust the cutting bits, and install the chip deflector.

5. NOTE: The depth of cut should be between 0.10 and 0.20 mm (0.004 and 0.008 inch). Lighter cuts will cause the bit to heat up and wear faster. Heavier cuts will cause poor brake disc surface finish.

Machine the brake disc.
6. Remove the lathe and, if installed, the silencer belt.
7. Remove the hub adapter.
7. Remove the metal shavings.
8. Remove the brake disc from the hub.
9. Remove metal shavings from the hub, the brake disc mounting surfaces and from the ABS wheel speed sensors.
10. Apply anti-seize lubricant to the hub mounting surface to prevent corrosion.
11. Align the match marks and install the brake disc on the hub.

12. NOTE: It is not required to install new brake pads if friction material properties are within guidelines.

Install the brake caliper and brake caliper anchor bracket

13. WARNING: If the vehicle is equipped with a fire suppression system, repower the system. For important safety warnings and procedures, refer to Fire Suppression System. Failure to follow these instructions may result in serious personal injury.

If equipped with fire suppression system, repower the system.