GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2004 🢒 TopKick C-Series (Conventional) C4/C5 🢒 Driveline/Axle 🢒 Rear Drive Axle 🢒 Two Speed Rear Axle Pressure Protection Valve Replacement

Removal Procedure
  1. Block the wheels.
  2. Drain all of the air reservoirs. Refer to Air Brake Reservoir Draining .

    3. Important: Tag the air lines for later installation.

  3. Remove the air lines at the two-speed rear axle pressure protection valve. Refer to Air Brakes.
  4. Remove the following components from the two-speed rear axle pressure protection valve:
    5. • The nuts
    • The washers
    • The bolts
  5. Remove the two-speed rear axle pressure protection valve at the brake pedal bracket.
  6. Inspect the air lines for the following conditions:
    7. • Damage
    • Kinks
    • Wear
  7. Repair or replace the air lines as needed. Refer to Hose and Line Replacement - Nylon Push-In Type Fitting .

Installation Procedure
  1. Install the two-speed rear axle pressure protection valve at the brake pedal bracket.

    2. Notice: Refer to Fastener Notice in the Preface section.

  2. Install the following components to the two-speed rear axle pressure protection valve:
    3. • The bolts
    • The washers
    • The nuts

    Tighten
    Tighten the two-speed rear axle pressure protection valve nuts to 12 N·m (106 lb in).

  3. Install the air lines at the two-speed rear axle pressure protection valve. Refer to Hose and Line Replacement - Nylon Push-In Type Fitting .
  4. Start the engine. Charge the system to the air compressor governor cutout point.
  5. Stop the engine.
  6. Inspect for air leaks using a soap solution.
  7. Remove the wheel blocks.