GM Service Manual Online
For 1990-2009 cars only

Heater Hoses Replacement 3.4L

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: 414214  Size: SH
  3. UseJ 38185 in order to position aside the heater hose inlet and/or outlet clamp.
  4. Disconnect the heater inlet hose and/or the outlet hose from the inlet and/or outlet pipe.

  5. Object Number: 414213  Size: SH
  6. UseJ 38185 in order to position aside the heater core inlet and/or outlet hose clamp.
  7. Disconnect the heater inlet hose and/or the outlet hose from the heater core.
  8. Remove the heater inlet hose and/or the outlet hose.

Installation Procedure

  1. Install the heater inlet hose and/or outlet hose.

  2. Object Number: 414213  Size: SH
  3. Connect the heater inlet hose and/or the outlet hose to the heater core.
  4. Important: Position heater core hose clamps in the indicated location.

  5. UseJ 38185 in order to secure the heater core hose inlet and/or outlet clamp.

  6. Object Number: 414214  Size: SH
  7. Connect the heater inlet hose and/or the outlet hose to the inlet and/or outlet pipe.
  8. UseJ 38185 in order to secure the heater hose inlet and/or outlet clamp.
  9. Refill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.

Heater Hoses Replacement 3.8L

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. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical 3.8L.

  3. Object Number: 415893  Size: SH
  4. UseJ 38185 in order to position aside the heater hose inlet and/or outlet clamp at the pipe adapter.
  5. Disconnect the heater inlet hose and/or the outlet hose from the pipe adapter.

  6. Object Number: 415890  Size: SH
  7. Remove the heater hose support bracket nut (1).

  8. Object Number: 415886  Size: SH
  9. UseJ 38185 in order to position aside the heater core inlet and/or outlet hose clamp.
  10. Disconnect the heater inlet hose and/or the outlet hose from the heater core.
  11. Separate the support bracket and remove the heater inlet hose and/or the outlet hose.

Installation Procedure

  1. Install the heater inlet hose and/or outlet hose and support bracket.

  2. Object Number: 415886  Size: SH
  3. Connect the heater inlet hose and/or the outlet hose to the heater core.
  4. Important: Position heater core hose clamps in the indicated location.

  5. UseJ 38185 in order to secure the heater core hose inlet and/or outlet clamp.

  6. Object Number: 415890  Size: SH
  7. Install the heater hose support bracket.
  8. 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.

  9. Install the support bracket nut (1).
  10. Tighten
    Tighten the heater core support bracket nut to 4.5 N·m (40 lb in).


    Object Number: 415893  Size: SH
  11. Connect the heater inlet hose and/or the outlet hose to the pipe adapter.
  12. UseJ 38185 in order to secure the heater hose inlet and/or outlet clamp.
  13. Install the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical 3.8L.
  14. Refill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.