Brake Pedal Assy: Testing and Inspection

Most low brake pedal problems are caused by air in the brake system or misadjusted rear drum brakes. Bleed the system until air is purged and check rear brake adjustment. Other less frequent causes of excessive brake pedal travel are incorrect pushrod length, rear brake shoe adjusters not operating, pads excessively worn, and brake hydraulic system leakage. High brake pedal effort problems are usually caused by low engine vacuum, a vacuum leak, or an improperly functioning vacuum booster.
1. Install J 28662 onto brake pedal.
2. Hook end of tape measure over top edge of pedal and measure the distance to rim of steering wheel.
3. With engine running at idle and the range selector lever in "NEUTRAL" and the wheels and tires blocked, apply brake pedal with 445 N (100 lb.) force and remeasure. The difference between both readings is actual brake pedal travel and should be between 51 to 89 mm (2.0 to 3.5 inches).
4. If brake pedal travel is more than specifications, refer to Brake Pedal Service and Repair.