Engine Block Heater: Service and Repair

Coolant Heater Replacement (LZ4 and LZ9) (3.5L and 3.9L)

Removal Procedure





1. Drain the cooling system. Refer to Cooling System Draining and Filling (LY7, LZ4, LZ9 Static Fill) (Service and Repair)Cooling System Draining and Filling (GE 47716 Fill) (Service and Repair)Cooling System Draining and Filling (LE5 Static Fill) (Service and Repair) .
2. Disconnect the engine coolant heater cord from the engine coolant heater.




3. Remove the engine coolant heater.
4. Clean the engine coolant heater opening.



Installation Procedure





1. Apply sealer GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the threads of the engine coolant heater, if necessary.
Notice: Refer to Fastener Notice .


2. Install the engine coolant heater.

Tighten the coolant heater to 60 N.m (44 lb ft).





3. Connect the engine coolant heater cord to the engine coolant heater.
4. Lower the vehicle.
5. Fill the cooling system. Refer to Cooling System Draining and Filling (LY7, LZ4, LZ9 Static Fill) (Service and Repair)Cooling System Draining and Filling (GE 47716 Fill) (Service and Repair)Cooling System Draining and Filling (LE5 Static Fill) (Service and Repair) .
6. Inspect for leaks.