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For 1990-2009 cars only

Engine Coolant Thermostat Replacement 3.8L Engine

Removal Procedure


    Object Number: 349798  Size: SH
  1. Remove the water outlet. Refer to Engine Coolant Thermostat Housing Replacement .
  2. Remove the engine coolant thermostat (3).

Installation Procedure


    Object Number: 349798  Size: SH
  1. Install the engine coolant thermostat (3).
  2. Install the water outlet. Refer to Engine Coolant Thermostat Housing Replacement .

Engine Coolant Thermostat Replacement 5.7L Engine

Removal Procedure

Important: The thermostat and thermostat housing MUST be replaced as an assembly. The thermostat is not serviceable separately.


    Object Number: 221671  Size: SH
  1. Open the radiator drain cock.
  2. Partially drain the radiator.

    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. Close the drain cock.
  4. Tighten
    Tighten the drain cock to 2 N·m (18 lb in).

  5. Reposition the radiator outlet hose clamp at the water pump.
  6. Remove the radiator outlet hose from the water pump inlet.

  7. Object Number: 370076  Size: SH
  8. Remove the water pump inlet bolts.
  9. Remove the water pump inlet.

  10. Object Number: 370073  Size: SH
  11. The O-ring seal is integral to the thermostat housing.
  12. Remove the thermostat.

Installation Procedure


    Object Number: 370073  Size: SH
  1. Install a new thermostat and housing.
  2. Ensure that the new thermostat housing has an O-ring seal and is in the groove correctly.

  3. Object Number: 370076  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.

  4. Install the water pump inlet and bolts.
  5. Tighten
    Tighten the water pump inlet bolts to 15 N·m (11 lb ft).


    Object Number: 221671  Size: SH
  6. Install the radiator outlet hose to the water pump inlet.
  7. Position the radiator outlet hose clamp at the water pump.
  8. Add coolant.