Initial Inspection and Diagnostic Overview

Special Tools:

Special Tool(s)

Inspection and Verification

Preliminary Checks

NOTE: Always check the fluid level in the brake master cylinder reservoir before carrying out the test procedures. If the fluid level is not at the correct level, fill the reservoir using the specified DOT 3 or DOT 4 brake fluid.

NOTE: Prior to carrying out any diagnosis, make certain that the brake warning indicator is functional.

A change in brake pedal feel is usually the first indicator of a brake system concern. The brake warning indicator in the instrument cluster and the brake fluid level in the brake master cylinder reservoir are also indicators of system concerns.
If a wheel is locked and the vehicle must be moved, open a bleeder screw at the locked wheel to let out enough fluid to relieve the pressure. Close the bleeder screw. This bleeding operation may release the brakes but will not correct the cause of trouble. If this does not relieve the locked wheel condition, repair the locked components before proceeding.

Visual Inspection Chart:

Visual Inspection Chart
For low or spongy brake pedal concerns:
^ Check and, if necessary, refill the brake master cylinder reservoir.
^ Bleed the brake system and retest the brake pedal feel.

For slow or incomplete brake pedal return concern:
^ Inspect for binding, damage, correct installation or interference at the brake pedal.
^ Check the power brake booster for binding, damage and correct installation.
^ Verify customer complaint.

Vibration When Brakes are Applied
For vibration concerns when brakes are applied, carry out the following procedure.
Visually inspect:
^ The suspension condition and tire pressure.
^ Suspension bushings and ball joints.

Correct as necessary.
1. Verify and isolate the concern. Brake vibration can be felt in:
^ the steering wheel.
^ the seat.
^ the brake pedal.

2. After verifying the concern, check for related concerns in the:
^ 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. Brake discs that require machining must be at least 0.5 mm (0.024 inch) above the minimum thickness specification to allow for machining. 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 the special tool, machine the brake discs. Follow the manufacturer's instructions. After machining, make sure the brake disc still meets the thickness specification.
9. Remove metal chips.
10. Remove the special tool hub adapter.
11. Remove any remaining metal chips from the machining operation.
12. For vehicles with a two-piece hub and 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 or equivalent meeting Ford specification ESE-M12A4-A to the mounting surfaces.
^ Using the match-marks, mount the brake disc on the hub.

13. Install the caliper and check brake operation.

Brake Booster
Inspect all hoses and connections. All unused vacuum connectors should be capped. Hoses and their connections should be correctly secured and in good condition with no holes, soft or collapsed areas.

Adjustable Brake Pedals
Check the fuse and electrical connectors. Make sure the cables are firmly connected.