GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 38185 Hose Clamp Pliers

Removal Procedure

  1. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.

  2. Object Number: 420668  Size: SH
  3. Disconnect the heater hose from the heater inlet pipe adapter using the J 38185 .

  4. Object Number: 420658  Size: SH
  5. Remove the bolt from the heater pipe adapter (1).
  6. Remove the heater inlet pipe adapter (1) from the engine.

Installation Procedure


    Object Number: 420658  Size: SH
  1. Install the heater inlet pipe adapter (1) to the engine.
  2. 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.

  3. Install the heater pipe adapter bolt.
  4. Tighten
    Tighten the bolt to 10 N·m (89 lb in).


    Object Number: 420668  Size: SH
  5. Connect the heater hose to the heater pipe adapter and reposition the clamp using the J 38185 .
  6. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.