Coolant Heater Replacement 8.1L Engine

1. Drain the cooling system. Refer to Cooling System Draining and Filling .
2. Disconnect the block heater cord from the block heater.



3. Remove the engine block heater.

1. Apply sealant GM P/N 12346004, Canadian P/N 10953480 or equivalent to the threads of the engine block heater.

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 engine block heater into the block.

Tighten
Tighten the engine block heater to 60 N·m (40 lb ft).





Notice: The heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Route the cord to the left front of the engine compartment securing with tie straps as necessary to prevent damage.

3. Connect the block heater cord to the block heater.
4. Fill the cooling system. Refer to Cooling System Draining and Filling .

Coolant Heater Replacement 4.8L, 5.3L, and 6.0L Engines

1. Drain the cooling system/engine block. Refer to Cooling System Draining and Filling .
2. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
3. Remove the oil pan skid plate bolts and plate.



4. Remove the oil cooler hose bracket bolt (1).
5. Remove the oil cooler hose adapter bolts (2).
6. Remove and discard the oil cooler hose adapter gasket.
7. Position the oil cooler hose adapter end out of the way.



8. Disconnect the coolant heater electrical connector (2).




Important: Do not score the surface of the engine block hole when removing the coolant heater.

9. Remove the coolant heater from the engine block.
10. Remove any burrs, sealer, or other rough spots.

1. If reusing the old coolant heater, apply thread sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the 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.

2. Install the coolant heater to the engine block.

Tighten
Tighten the coolant heater to 50 N·m (37 lb ft).





Notice: The heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Route the cord to the left front of the engine compartment securing with tie straps as necessary to prevent damage.

3. Connect the coolant heater electrical connector (2).



4. Position the oil cooler hose adapter end.
5. Install a NEW oil cooler hose adapter gasket.
6. Install the oil cooler hose adapter bolts (2).

Tighten
Tighten the oil cooler hose adapter bolts to 12 N·m (106 lb in).

7. Install the oil cooler hose bracket bolt (1).

Tighten
Tighten the oil cooler hose bracket bolt to 25 N·m (18 lb ft).




8. Install the oil pan skid plate and bolts.

Tighten
Tighten the oil pan skid plate bolts to 20 N·m (15 lb ft).

9. Lower the vehicle.
10. Fill the cooling system/engine block. Refer to Cooling System Draining and Filling .

Coolant Heater Replacement Dealer Installation - 6.0L Engine

1. Drain the cooling system/engine block. Refer to Cooling System Draining and Filling .
2. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
3. Remove the oil pan skid plate bolts and plate.



4. Remove the oil cooler hose bracket bolt (1).
5. Remove the oil cooler hose adapter bolts (2).
6. Remove and discard the oil cooler hose adapter gasket.
7. Position the oil cooler hose adapter end out of the way.




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.

8. Install the coolant heater in place of the drain plug.

Tighten
Tighten the coolant heater to 50 N·m (37 lb ft).




9. Push the engine coolant heater cord electrical connector (2) firmly into the coolant heater (1).

Important: The engine coolant heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Always keep the electrical cord neatly rolled up with the end of the cord tucked in the center of the coil and secured in place.




10. Place the cord into position.

Notice: The heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Route the cord to the left front of the engine compartment securing with tie straps as necessary to prevent damage.

11. Install the heater cord bolt and retainer.

Tighten
Tighten the heater cord bolt to 8 N·m (71 lb in).




12. Position the oil cooler hose adapter.
13. Install a NEW oil cooler hose adapter gasket.
14. Install the oil cooler hose adapter bolts (2).

Tighten
Tighten the oil cooler hose adapter bolts to 12 N·m (106 lb in).

15. Install the oil cooler hose bracket bolt (1).

Tighten
Tighten the oil cooler hose bracket bolt to 25 N·m (18 lb ft).




16. Install the oil pan skid plate and bolts.

Tighten
Tighten the oil pan skid plate bolts to 20 N·m (15 lb ft).

17. Lower the vehicle.
18. Fill the cooling system/engine block. Refer to Cooling System Draining and Filling .