For 1990-2009 cars

### Removal Procedure

1. Drain the cooling system. Refer to Cooling System Draining and Filling .
2. Remove the intake plenum. Refer to Intake Plenum Replacement in Engine Mechanical - 3.0L.
3. Remove the intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical - 3.0L.
4. Remove the power steering reservoir bracket bolt and the power steering reservoir bracket.
5. Reposition the power steering reservoir.
6. Remove the radiator inlet hose clamp from the thermostat outlet pipe.
7. Remove the radiator inlet hose (1) from the thermostat outlet pipe.
8. Remove the thermostat outlet pipe bolt (1).
9. Remove the thermostat outlet pipe (2).
10. Discard the O-rings.
11. Remove the O-ring seals from the thermostat outlet pipe.
12. Discard the O-rings.
13. Remove the thermostat housing bolts (1).
14. Remove the thermostat housing (2).
15. Remove and discard the seal ring.

### Installation Procedure

1. Install a new seal ring.
2. Install the thermostat with the thermostat outlet housing (2) to the engine.
3. Apply sealant GM P/N 12346004 (Canadian P/N 10953480) to the thermostat housing bolt threads.

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 thermostat outlet housing bolts (1).

Tighten
Tighten the thermostat outlet housing bolts to 20 N·m (15 lb ft).

5. Lubricate two new O-rings with coolant.
6. Install the new O-rings in the thermostat outlet pipe.
7. Install the thermostat outlet pipe (2).
8. Install the thermostat outlet pipe bolt (1).

Tighten
Tighten the thermostat outlet pipe bolt to 20 N·m (15 lb ft).

9. Install the radiator inlet hose (1) to the thermostat outlet pipe.
10. Install the radiator inlet hose clamp to the thermostat outlet pipe.
11. Install the power steering reservoir and the power steering reservoir bracket.
12. Install the power steering reservoir bracket bolt.

Tighten
Tighten the power steering reservoir bracket bolt to 7 N·m (62 lb in).

13. Install the intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical - 3.0L.
14. Install the intake plenum. Refer to Intake Plenum Replacement in Engine Mechanical - 3.0L.
15. Fill the cooling system. Refer to Cooling System Draining and Filling .