Ford Mustang (1999-2004) Service Manual: Vibration When Brakes are Applied

For vibration concerns when brakes are applied, perform the following procedure.

Visually inspect:

• tire condition and pressure.
• suspension bushings and ball joints.

Correct as necessary.

1. Verify and isolate the concern. Brake roughness can be felt in:

• the steering wheel.
• the seat.
• the brake pedal.

2. After verifying the concern, check for related concerns in the:

• On-Line Automotive Service Information System (OASIS).
• Technical Service Bulletins.

3. Check wheel bearing end-play and correct as necessary.

4. NOTE: Begin at the front of the vehicle unless the vibration has been isolated to the rear.

Remove the tire and wheel.

5. Remove the brake caliper.

6. Measure and record the brake disc thickness. Install a new brake disc if the thickness after machining will be at or below specification. The specification is molded into the brake disc. Do not machine a new brake disc.

7. For vehicles with a two-piece hub and brake disc assembly:

• Match-mark before disassembly.
• Remove the brake disc.
• Using a die grinder with a mild abrasive (Scotch Brite type), remove any rust or corrosion from the hub and brake disc mounting surfaces.
• Align the match-marks and reinstall the brake disc on the hub.

8. CAUTION: Do not use a bench lathe to machine brake discs.

NOTE: The depth of cut must be between 0.10 and 0.20 mm (0.004 and 0.008 inch). Lighter cuts will cause heat and wear. Heavier cuts will cause poor brake disc surface finish.

Using on-vehicle brake lathe, machine the brake discs. Follow the manufacturer's instructions.

After machining, make sure the brake disc still meets the thickness specification.

9. Using a dial indicator, verify that the brake disc lateral runout is now within vehicle specification.

10. Remove any metal chips.

11. Remove the hub adapter.

12. Remove any remaining metal chips from the machining operation.

13. CAUTION: Do not carry out this step on rear drum-in-hat brake discs.

For vehicles with a two-piece hub and a non drum-in-hat brake disc assembly:

• Remove the brake disc from the hub.
• Remove any remaining metal chips from hub and brake disc mounting surfaces and from the ABS sensor.
• Apply High Temperature Nickel Anti-Seize Lubricant F6AZ-9L494-AA to the mounting surfaces.
• Using the match-marks, mount the brake disc on the hub.

14. Install the caliper and check brake operation.