GM Service Manual Online
For 1990-2009 cars only

Heater Pipes Replacement LS4

Special Tools

J 38185 Spring Hose Clamp Pliers

Removal Procedure

  1. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement.
  2. Drain the cooling system. Refer to Cooling System Draining and Filling.

  3. Object Number: 1524231  Size: SH
  4. Release and reposition the heater inlet and outlet hose clamps using the J 38185 .
  5. Note: Cap or plug the cooling components to prevent system contamination.

  6. Remove the heater hoses from heater pipes.

  7. Object Number: 1524232  Size: SH

    Caution: Do not apply excessive force on the heater core pipes during hose removal. Applying excessive force on the heater core pipes may damage the heater core pipes.

  8. Remove the heater pipe assembly retaining bolts from the rear the of engine.

  9. Object Number: 1524235  Size: SH
  10. Remove the heater pipe assembly retaining bolt from the front of the engine.
  11. Release and reposition the heater pipe hose clamps at the engine using the J 38185 .
  12. Remove the heater pipe hoses from the engine.
  13. Remove the heater pipe assembly from the vehicle.

Installation Procedure


    Object Number: 1524235  Size: SH
  1. Using a lint-free clean, dry cloth, carefully clean the sealing surfaces of the heater pipe assembly at the engine and heater hoses.
  2. Install the heater pipe assembly into position in the vehicle.
  3. Install the heater pipe hoses to the engine.
  4. Reposition and release the heater pipe hose clamps at the engine using the J 38185 .
  5. Loosely install the heater pipe assembly retaining bolt to the front of the engine.
  6. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1524232  Size: SH
  7. Install the heater pipe assembly retaining bolts to the rear of the engine.
  8. Tighten
    Tighten all the heater pipe assembly bolts to 16 N·m (12 lb ft).


    Object Number: 1524231  Size: SH
  9. Connect heater hoses to the heater pipe assembly.
  10. Install the heater hose clamps into position using the J 38185 .
  11. Install the air cleaner assembly. Refer to Air Cleaner Assembly Replacement.
  12. Fill the cooling system. Refer to Cooling System Draining and Filling.