Coolant Heater Replacement LY7

1. Turn the ignition OFF.
2. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
3. Remove the rear transmission Mount. Refer to Transmission Rear Mount Replacement
4. Disconnect the coolant heater cord from the coolant heater.



5. Remove the coolant heater.

1. Install the coolant heater.
2. Connect the coolant heater cord to the coolant heater.
3. Install the rear transmission Mount. Refer to Transmission Rear Mount Replacement
4. Lower the vehicle.

Coolant Heater Replacement LNJ

1. Drain the engine coolant. Refer to Cooling System Draining and Filling.
2. Remove the coolant heater cord from the heater.

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

3. Remove the coolant heater from the block.

1. Remove any burrs, sealer, paint or other foreign material from the threads/sealing surface of the engine block and from the old coolant heater if the heater is to be reused.
2. If reusing the old coolant heater, apply thread sealant GM P/N 12346004 (Canadian P/N 10953480), or equivalent to the threads.

Caution: Refer to Component Fastener Tightening Caution in the Preface section.

3. Install the coolant heater to the engine block. Tighten the coolant heater to 50 N·m (37 lb ft).
4. Install the coolant heater cord to the heater.
5. Fill the cooling system. Refer to Cooling System Draining and Filling.