GM Service Manual Online
For 1990-2009 cars only

Most low brake pedal problems are caused by air in the hydraulic system. Bleed the system until all air is purged. Refer to Hydraulic Brake System Bleeding . Other less frequent causes of excessive pedal travel are excessively worn linings and hydraulic system leakage. At reasonably frequent intervals, the brakes should be measured for pedal travel, which is the distance the pedal moves toward the floor from a fully released position.

  1. With the engine off, pump the brake pedal a minimum of three times to exhaust the vacuum assist from the power brake booster.
  2. Hook the end of a tape measure over the top edge of the brake pedal and measure the distance to the rim of the steering wheel.
  3. Depress the brake pedal with approximately 310 N (70 lb) of force while brakes are cold and measure. Pedal travel should not exceed 70 mm (2.75 in).