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Coolant Heater Replacement




Coolant Heater Replacement (LH6) (5.3L)

Removal Procedure




1. Drain the cooling system. Refer to Cooling System Draining and Filling (LH6) (Cooling System Draining and Filling)Cooling System Draining and Filling (LL8) (Cooling System Draining and Filling).
2. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle (Service and Repair).
3. Disconnect the coolant heater (1) electrical connector.





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

4. Remove the coolant heater from the engine block.
5. Remove any burrs, sealer, paint or other rough spots.

Installation Procedure




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

Caution: Refer to Fastener Caution (Fastener Caution).

2. Install the coolant heater to the engine block and tighten to 50 Nm (37 ft. lbs.).





Caution: 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 (1) electrical connector.
4. Lower the vehicle.
5. Fill the cooling system. Refer to Cooling System Draining and Filling (LH6) (Cooling System Draining and Filling)Cooling System Draining and Filling (LL8) (Cooling System Draining and Filling).