GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2000 🢒 GMC C Pickup - 2WD 🢒 Engine 🢒 Engine Mechanical - 6.5L 🢒 Engine Coolant Thermostat Installation

    Object Number: 66572 Size: SH
  1. Install the thermostat bypass connector.
  2. Install the thermostat bypass hose and clamps.
  3. Install the thermostat housing and gaskets.

    4. 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 bolts and stud/nut.

    5. Tighten
    Tighten the bolts and the stud/nut to 42 N·m (31 lb ft).

  5. Install the engine coolant temperature (ECT) sensor.
  6. Install the fuel bleed valve and stud/nut.

    7. Tighten
    Tighten the stud/nut to 41 N·m (31 lb ft).


    Object Number: 64991 Size: SH
  7. Install the seals (3) onto the thermostats (2).
    8. • The seals have a split, inner edge, which install over the flange on the thermostats.
    • The seals have a bead on the surface that faces the water outlet.
  8. Install the thermostats in the thermostat housing.
  9. Install the water outlet.
  10. Install the bolts/studs.

    11. Tighten
    Tighten the bolts/studs to 47 N·m (35 lb ft).