GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2004 🢒 TopKick C-Series (Conventional) C4/C5 🢒 Engine 🢒 Engine Mechanical - 6.6L (LB7) 🢒 Engine Coolant Thermostat Housing Installation

    Object Number: 813908 Size: SH
  1. Install the oil level sensor harness.

    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.

  2. Install the ground bolt to the left side of the block.

    3. Tighten
    Tighten the ground bolt to 34 N·m (25 lb ft).

  3. Connect the oil pressure sensor connector.

    4. Object Number: 755218 Size: SH
  4. Install the turbocharger coolant outlet pipe.
  5. Install the turbocharger coolant outlet pipe bracket bolts.

    6. Tighten
    Tighten the turbocharger coolant outlet pipe bracket bolts to 21 N·m (15 lb ft).


    Object Number: 660428 Size: SH
  6. Install a new O-ring to the bypass pipe. Lubricate the O-ring with engine coolant.
  7. Install the bypass pipe to the thermostat housing.

    8. Object Number: 660426 Size: SH
  8. Install new thermostat housing gaskets.
  9. Install the thermostat housing with the bypass pipe.
  10. Install the bypass pipe to water pump bolts.

    11. Tighten
    Tighten the bypass pipe to water pump bolts to 21 N·m (15 lb ft).


    Object Number: 793975 Size: SH
  11. Install the thermostat housing bolts and nuts.

    12. Tighten
    Tighten the thermostat housing bolts and nuts in sequence to 25 N·m (18 lb ft).

  12. Install the right fuel rail high pressure pipe to the thermostat housing bracket bolt.

    13. Tighten
    Tighten the high pressure pipe bracket bolt to 21 N·m (15 lb ft).


    Object Number: 798886 Size: SH
  13. Install a new O-ring on the heater pipe. Lubricate the O-ring with engine coolant.
  14. Install the heater pipe.
  15. Install the heater pipe bracket bolt.

    16. Tighten
    Tighten the heater pipe bracket bolt to 21 N·m (15 lb ft).

  16. Install the heater pipe to thermostat housing bolt.

    17. Tighten
    Tighten the heater pipe to thermostat housing bolt to 21 N·m (15 lb ft).


    Object Number: 798885 Size: SH
  17. Install the thermostats.
  18. Install the thermostat cover and gasket.
  19. Install the thermostat cover bolts.

    20. Tighten
    Tighten the thermostat cover bolts to 21 N·m (15 lb ft).

  20. Install a new o-ring to the water outlet pipe.
  21. Lubricate the water outlet pipe o-ring with engine coolant.
  22. Install the water outlet pipe.
  23. Install the water outlet pipe bolts.

    24. Tighten
    Tighten the water outlet pipe bolts to 21 N·m (15 lb ft).