GM Service Manual Online
For 1990-2009 cars only

Coolant Heater Replacement LS4

Removal Procedure


    Object Number: 1411869  Size: SH
  1. Drain the cooling system. Refer to Cooling System Draining and Filling.
  2. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  3. Disconnect the coolant heater cord from the coolant heater.
  4. Remove the coolant heater (114) and washer (115).
  5. Remove and clean any burrs, compound, paint, or rough spots from the core plug hole.

Installation Procedure


    Object Number: 1411869  Size: SH
  1. Apply a 3.175 mm (0.125 in) bead of sealant, GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the coolant heater.
  2. Caution: Refer to Fastener Caution in the Preface section.

  3. Install the coolant heater (114) and washer (115).
  4. Tighten
    Tighten the coolant heater to 50 N·m (37 lb ft).

  5. Connect the coolant heater cord to the coolant heater.
  6. Lower the vehicle.
  7. Fill the cooling system. Refer to Cooling System Draining and Filling.

Coolant Heater Replacement LZE, LZ4, LZG

Removal Procedure


    Object Number: 1616612  Size: SH
  1. Drain the cooling system. Refer to Cooling System Draining and Filling.
  2. Disconnect the engine coolant heater cord (2) from the engine coolant heater.

  3. Object Number: 1584087  Size: SH
  4. Remove the engine coolant heater.
  5. Clean the engine coolant heater opening.

Installation Procedure

    Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1584087  Size: SH
  1. Apply sealer GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the threads of the engine coolant heater, if necessary.
  2. Install the engine coolant heater.
  3. Tighten
    Tighten the coolant heater to 60 N·m (44 lb ft).


    Object Number: 1616612  Size: SH
  4. Connect the engine coolant heater cord (2) to the engine coolant heater.
  5. Lower the vehicle.
  6. Fill the cooling system. Refer to Cooling System Draining and Filling.
  7. Inspect for leaks.