GM Service Manual Online
For 1990-2009 cars only

    Important: There were two types of thermostat housings used during the model year. An engine may have either dual thermostats or a single thermostat.

  1. Install the thermostat.

  2. Object Number: 59782  Size: SH
  3. If the engine has dual thermostats, install the seals.
  4. • With a dual thermostat type engine, install the seals on the thermostats before installation.
    • 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 thermostat housing.

    Object Number: 59780  Size: SH
  5. If the engine has a single thermostat, install the gasket.

  6. Object Number: 59779  Size: SH
  7. Install the thermostat housing.

  8. Object Number: 59777  Size: SH
  9. Install the bolts/studs.
  10. Tighten
    Tighten the bolts/studs to 47 N·m (35 lb ft).

    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.