Tools Required

J 28662 Brake Pedal Effort Gauge

1. With the engine off and the key OFF, pump the service brake pedal until all reserve is exhausted from the brake booster.
2. Install the J 28662 or the equivalent onto the brake pedal.
3. Hook the end of the tape measure over the top edge of the pedal.
4. Measure the distance from the top edge of the brake pedal to the rim of the steering wheel.
5. Depress the service brake pedal with approximately 445 N 100 lbs of force.
6. Re-measure the distance from the top edge of the brake pedal to the rim of the steering wheel. The difference between both readings is the actual pedal travel and should not exceed 63 mm (2.5 in).
7. If the pedal travel is greater than 63 mm (2.5 in), drive the vehicle backward while intermittently applying the brakes. In rare cases, excessive pedal travel will develop if brakes are only used occasionally when backing up. This will develop when the vehicle is only driven in reverse. Duo-Servo self-adjusting mechanisms will only actuate when the brakes are applied in reverse.
8. Air in the hydraulic system may be the cause of most low pedal problems. Bleed the system until all of the air is purged. Refer to Hydraulic Brake System Bleeding .
9. Other less frequent causes of excessive brake travel include the following conditions:

•	Incorrect brake booster pushrod length

•	Improperly adjusted parking brake

•	Rear shoe adjusters not functioning

•	Excessively worn brake shoes

•	Hydraulic system leakage