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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2008 🢒 Yukon XL Denali 🢒 General Information 🢒 General Information 🢒 Coolant Heater Replacement

Coolant Heater Replacement RPOs LC9/L76/L92

Removal Procedure

    Object Number: 1698082 Size: SH
  1. Drain the cooling system/engine block. Refer to Cooling System Draining and Filling .
  2. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  3. Remove the oil pan skid plate bolts and plate, if equipped.

    4. Object Number: 1702199 Size: SH
  4. For vehicles with regular production option (RPO) L76 (6.0L), perform the following steps. Otherwise, proceed to step 9.
  5. Remove the oil cooler hose bracket bolt (1), if equipped.
  6. Remove the oil cooler hose adapter bolts (2), if equipped.
  7. Remove and discard the oil cooler hose adapter gasket, if equipped.
  8. Position the oil cooler hose adapter end out of the way, if equipped.

    9. Object Number: 1699547 Size: SH
  9. Disconnect the coolant heater cord electrical connector.

    10. Object Number: 1702201 Size: SH

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

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

Installation Procedure

    Object Number: 1702201 Size: SH
  1. If reusing the old coolant heater, apply thread sealant GM P/N 12346004 (Canadian P/N 10953480), or equivalent to the threads.

    2. Notice: Refer to Fastener Notice in the Preface section.

  2. Install the coolant heater to the engine block.

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


    Object Number: 1699547 Size: SH
  3. Connect the coolant heater cord electrical connector.

    4. Object Number: 1702199 Size: SH
  4. For vehicles with RPO L76 (6.0L) perform the following steps otherwise proceed to step 9.
  5. Position the oil cooler hose adapter end, if equipped.
  6. Install a NEW oil cooler hose adapter gasket, if equipped.
  7. Install the oil cooler hose adapter bolts (2), if equipped.

    8. Tighten
    Tighten the bolts to 12 N·m (106 lb in).

  8. Install the oil cooler hose bracket bolt (1), if equipped.

    9. Tighten
    Tighten the bolt to 25 N·m (18 lb ft).


    Object Number: 1698082 Size: SH
  9. Position and install the oil pan skid plate and bolts, if equipped

    10. Tighten
    Tighten the bolts to 20 N·m (15 lb ft).

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

Coolant Heater Replacement RPOs LY2/LMG/LY5/LY6

Removal Procedure

    Object Number: 1698082 Size: SH
  1. Drain the cooling system/engine block. Refer to Cooling System Draining and Filling .
  2. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  3. For 1500 series vehicles, remove the oil pan skid plate bolts and plate, if equipped.

    4. Object Number: 1698083 Size: SH
  4. For 2500 series vehicle, remove the front 2 oil pan skid plate bolts, loosen the 2 rear bolts and remove the skid plate, if equipped.

    5. Object Number: 1702200 Size: SH
  5. For vehicles with regular production option (RPO) LY6 (6.0L) perform the following steps otherwise proceed to step 10.
  6. Remove the oil cooler hose bracket bolt (1).
  7. Remove the oil cooler hose adapter bolts (2).
  8. Remove and discard the oil cooler hose adapter gasket.
  9. Reposition the oil cooler hose adapter end out of the way.

    10. Object Number: 1699548 Size: SH
  10. Disconnect the coolant heater cord electrical connector.

    11. Object Number: 1702202 Size: SH

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

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

Installation Procedure

    Object Number: 1702202 Size: SH
  1. If reusing the old coolant heater, apply thread sealant GM P/N 12346004 (Canadian P/N 10953480), or equivalent to the threads.

    2. Notice: Refer to Fastener Notice in the Preface section.

  2. Install the coolant heater to the engine block.

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


    Object Number: 1699548 Size: SH
  3. Connect the coolant heater cord electrical connector.

    4. Object Number: 1702200 Size: SH
  4. For vehicles with RPO LY6 (6.0L) perform the following steps otherwise proceed to step 9.
  5. Position the oil cooler hose adapter end.
  6. Install a NEW oil cooler hose adapter gasket.
  7. Install the oil cooler hose adapter bolts (2).

    8. Tighten
    Tighten the bolts to 12 N·m (106 lb in).

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

    9. Tighten
    Tighten the bolt to 25 N·m (18 lb ft).


    Object Number: 1698083 Size: SH
  9. For 2500 series vehicles, position the oil pan skid plate and install the 2 front bolts and tighten the 2 rear bolts, if equipped.

    10. Tighten
    Tighten the bolts to 20 N·m (15 lb ft).


    Object Number: 1698082 Size: SH
  10. For 1500 series vehicles position and install the oil pan skid plate and bolts, if equipped.

    11. Tighten
    Tighten the bolts to 20 N·m (15 lb ft).

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