GM Service Manual Online
For 1990-2009 cars only

Reservoir Drain Valve Replacement Primary Air Brake-Manual Type

Removal Procedure

  1. Apply the parking brake.
  2. Block the wheels.
  3. Drain all the reservoirs. Refer to Draining Reservoirs .

  4. Object Number: 201690  Size: SH
  5. Remove the reservoir drain valve.

Installation Procedure


    Object Number: 201690  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  1. Install the reservoir drain valve (manual type).
  2. Tighten
    Tighten the primary air brake supply reservoir drain valve to 50 N·m (37 lb ft).

  3. Start the engine.
  4. Charge the system air pressure to the governor cut-out point.
  5. Check for leaks with a soap solution around the reservoir drain valve.
  6. Leakage is not permissible.

  7. Remove the wheel blocks.

Reservoir Drain Valve Replacement Front Axle-Manual Type

Removal Procedure

  1. Apply the parking brake.
  2. Block the wheels.
  3. Drain all the reservoirs. Refer to Draining Reservoirs .

  4. Object Number: 201688  Size: SH
  5. Remove the reservoir drain valve.

Installation Procedure


    Object Number: 201688  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  1. Install the reservoir drain valve (manual type).
  2. Tighten
    Tighten the front axle service reservoir drain valve to 50 N·m (37 lb ft).

  3. Start the engine.
  4. Charge the system air pressure to the governor cut-out point.
  5. Check for leaks with a soap solution around the reservoir drain valve.
  6. Leakage is not permissible.

  7. Remove the wheel blocks.

Reservoir Drain Valve Replacement Rear Axle-Manual Type

Removal Procedure

  1. Apply the parking brake.
  2. Block the wheels.
  3. Drain all the reservoirs. Refer to Draining Reservoirs .

  4. Object Number: 201686  Size: SH
  5. Remove the reservoir drain valve.

Installation Procedure


    Object Number: 201686  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  1. Install the reservoir drain valve (manual type).
  2. Tighten
    Tighten the rear axle service reservoir drain valve to 50 N·m (37 lb ft).

  3. Start the engine.
  4. Charge the system air pressure to the governor cut-out point.
  5. Check for leaks with a soap solution around the reservoir drain valve.
  6. Leakage is not permissible.

  7. Remove the wheel blocks.

Reservoir Drain Valve Replacement Secondary Air Brake-Manual

Removal Procedure

  1. Apply the parking brake.
  2. Block the wheels.
  3. Drain all of the reservoirs. Refer to Draining Reservoirs .
  4. Remove the reservoir drain valve (manual type).

Installation Procedure

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  1. Install the reservoir drain valve (manual type).
  2. Tighten

        • Tighten the primary air brake supply reservoir drain valve (manual type) to 50 N·m (37 lb ft).
        • Tighten the front axle service reservoir drain valve (manual type) to 50 N·m (37 lb ft).
        • Tighten the rear axle service reservoir drain valve (manual type) to 50 N·m (37 lb ft).
  3. Start the engine.
  4. Charge the system air pressure to the governor cut-out point.
  5. Inspect for leaks using a soap solution around the reservoir drain valve (manual type).
  6. No leakage is allowed.
  7. Remove the wheel blocks.