GM Service Manual Online
For 1990-2009 cars only

Air Conditioning Compressor Replacement LS4

Tools Required

J 39400-A Halogen Leak Detector

Removal Procedure

  1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  2. Remove the drive belt. Refer to Drive Belt Replacement - Accessory .
  3. Remove the lower radiator air baffle and deflector. Refer to Radiator Air Lower Baffle and Deflector Replacement .
  4. Remove the engine splash shield. Refer to Engine Splash Shield Replacement .

  5. Object Number: 1548455  Size: SH
  6. Disconnect the A/C compressor electrical connector.

  7. Object Number: 1548415  Size: SH
  8. Remove the A/C compressor hose nut from the A/C compressor.

  9. Object Number: 1548414  Size: SH

    Important: Remove and discard all sealing washers.

  10. Remove the A/C compressor hose from the A/C compressor.

  11. Object Number: 1548471  Size: SH
  12. Remove the stud from the A/C compressor.

  13. Object Number: 1548417  Size: SH
  14. Loosen the rear mounting bolt from the A/C compressor.

  15. Object Number: 1548416  Size: SH
  16. Remove the front mounting bolt from the A/C compressor.
  17. Remove the front mounting nut from the A/C compressor.
  18. Remove the front A/C compressor mounting stud.
  19. Install a floor stand under the right front cradle.
  20. Loosen the right front cradle bolt and lower the cradle.
  21. Remove the A/C compressor.
  22. Important: Replacement compressors are shipped with polyalkylene glycol (PAG) oil

  23. If replacing the compressor, balance the compressor oil. Refer to Air Conditioning Compressor Oil Balancing .

Installation Procedure

    Notice: Refer to Fastener Notice in the Preface section.

  1. Install the compressor drain plug.
  2. Tighten
    Tighten the drain plug to 16 N·m (12 lb ft).


    Object Number: 1548417  Size: SH

    Important: Install the A/C compressor ensuring that the back of the A/C compressor is inserted onto the bolt. Do not tighten the bolt at this time.

  3. Install the A/C compressor into the vehicle.

  4. Object Number: 1548416  Size: SH

    Important: Do not tighten at this time.

  5. Install the front A/C compressor mounting bolt.
  6. Install the front A/C compressor mounting stud.
  7. Tighten
    Tighten the stud to 10 N·m (89 lb in).

  8. Install the front A/C compressor nut.
  9. Tighten

        • Tighten the nut to 50 N·m (36 lb ft).
        • Tighten the front bolt to 50 N·m (36 lb ft).
        • Tighten the rear bolt to 50 N·m (36 lb ft).

    Object Number: 1548455  Size: SH
  10. Connect the A/C compressor electrical connector.
  11. Raise the cradle into position and tighten the bolt.
  12. Tighten
    Tighten the bolt to 145 N·m (107 lb ft).

  13. Remove the floor stand from under the vehicle.

  14. Object Number: 1548471  Size: SH
  15. Install the stud to the back of the A/C compressor.
  16. Tighten
    Tighten the stud to 10 N·m (89 lb in).


    Object Number: 1548414  Size: SH
  17. Install new sealing washers. Refer to Sealing Washer Replacement .
  18. Install the A/C compressor hose to the A/C compressor.

  19. Object Number: 1548415  Size: SH
  20. Install the A/C compressor hose nut.
  21. Tighten
    Tighten the nut to 17 N·m (12.5 lb ft).

  22. Install the lower radiator air baffle and deflector. Refer to Radiator Air Lower Baffle and Deflector Replacement .
  23. Install the drive belt. Refer to Drive Belt Replacement - Accessory .
  24. Install the engine splash shield. Refer to Engine Splash Shield Replacement .
  25. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
  26. Leak test the fittings of the component using J 39400-A .

Air Conditioning Compressor Replacement L26, L32

Tools Required

J 39400-A Halogen Leak Detector

Removal Procedure

  1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  2. Important: The supercharged L32 engine utilizes two drive belts. The outer drive belt drives the supercharger. Only release the drive belt tension from the accessories drive belt tensioner.

  3. Release the drive belt tension by lifting or rotating the drive belt tensioner using a 15mm box end wrench on the pulley nut.
  4. Remove the drive belt from the A/C compressor pulley and position the drive belt aside.
  5. Slowly release the tension from the drive belt tensioner and remove the box end wrench.
  6. Remove the splash shield from the right side of the engine. Refer to Engine Splash Shield Replacement .
  7. Remove the hose nut from the A/C compressor.
  8. Remove the hose from the A/C compressor.
  9. Important: Remove and discard all sealing washers.

  10. Disconnect the electrical connector from the A/C compressor.

  11. Object Number: 1199944  Size: SH
  12. Loosen the rear mounting bolt from the A/C compressor.
  13. Remove the front mounting bolt from the A/C compressor.
  14. Remove the front mounting nut from the A/C compressor.
  15. Remove the A/C compressor.
  16. Important: Replacement compressors are shipped with polyalkylene glycol (PAG) oil

  17. If replacing the compressor, balance the compressor oil. Refer to Air Conditioning Compressor Oil Balancing .

Installation Procedure

    Notice: Refer to Fastener Notice in the Preface section.

  1. Install the compressor drain plug.
  2. Tighten
    Tighten the drain plug to 16 N·m (12 lb ft).

  3. Position the A/C compressor on to the front A/C compressor mounting stud, and the rear A/C compressor mounting bolt.
  4. Install the A/C compressor front bolt.
  5. Tighten
    Tighten the bolts to 50 N·m (36 lb ft).

  6. Install the A/C compressor front mounting nut.
  7. Tighten
    Tighten the nut to 50 N·m (36 lb ft).

  8. Tighten the A/C compressor rear bolt.
  9. Tighten
    Tighten the bolt to 50 N·m (36 lb ft).

  10. Install new sealing washers. Refer to Sealing Washer Replacement .

  11. Object Number: 1199944  Size: SH
  12. Install the hose to the A/C compressor.
  13. Install the nut to the A/C compressor hose.
  14. Tighten
    Tighten the nut to 17 N·m (13 lb ft).

  15. Connect the electrical connector to the A/C compressor.
  16. Install the splash shield to the right side of the engine. Refer to Engine Splash Shield Replacement .
  17. Release the drive belt tension by lifting or rotating the drive belt tensioner using a 15 mm box end wrench.
  18. Install the drive belt around the A/C compressor pulley.
  19. Important: Verify that the drive belt is aligned into the proper grooves of all pulleys.

  20. Slowly release the tension from the drive belt tensioner and remove the box end wrench.
  21. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
  22. Leak test the fittings of the component using J 39400-A .