GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2009 🢒 TopKick C-Series (Conventional) C4/C5 🢒 Brakes 🢒 Air Brakes 🢒 Rear Air Brake Relay Double Check Valve Replacement

Removal Procedure
  1. Block the wheels.
  2. Drain all of the air reservoirs. Refer to Air Brake Reservoir Draining.
  3. Tag or label the lines for installation.
  4. Remove the air lines from the relay double check valve. Refer to Hose and Line Replacement - Nylon Push-In Type Fitting.

    5. Object Number: 227936 Size: SH
  5. Remove the relay double check valve.
  6. Inspect the air lines for the following conditions:
    7. • Damage
    • Kinks
    • Wear
  7. Replace any damaged, kinked, or worn air lines.

Installation Procedure
  1. Install the relay double check valve.

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


    Object Number: 227936 Size: SH
  2. Install the following components:
    3. • The bolts

    Tighten
    Tighten the relay valve bolts to 52 N·m (38 lb ft).

    • The washers
    • The nuts
  3. Install the air lines to the relay double check valve. Refer to Hose and Line Replacement - Nylon Push-In Type Fitting.
  4. Perform the air leakage test. Refer to Rear Relay Double Check Valve Operational Check.
  5. Perform the operational test. Refer to Rear Relay Double Check Valve Leakage Test.
  6. Remove the wheel blocks.