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

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

  8. Object Number: 1548414  Size: SH

    Important: Remove and discard all sealing washers.

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

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

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

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

  22. 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. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
  25. Leak test the fittings of the component using J 39400-A .

Air Conditioning Compressor Replacement LZE, LZ4, LZG


Object Number: 1606802  Size: MF

Callout

Component Name

Preliminary Procedures

  1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  2. Remove the drive belt. Refer to Drive Belt Replacement for the 3.5L engine or Drive Belt Replacement for the 3.9L engine.
  3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  4. Remove the right engine splash shield. Refer to Engine Splash Shield Replacement .
  5. Disconnect the electrical connector.

1

A/C Compressor Hose Nut

Notice: Refer to Fastener Notice in the Preface section.

Tip
Remove the A/C compressor hose from the A/C compressor and cap hose.

Tighten
17 N·m (12.5 lb ft)

2

Sealing Washer

Tip
Remove and discard sealing washers. Refer to Sealing Washer Replacement .

3

A/C Compressor Nut

Tip
Tighten in sequence with A/C compressor mounting bolts.

Tighten
50 N·m (37 lb ft)

4

A/C Compressor Bolt

Tip
Tighten the A/C compressor mounting bolts and nut in sequence.

Tighten
50 N·m (37 lb ft)

5

A/C Compressor Assembly

Procedure

  1. Use a low viscosity, polyalkylene glycol (PAG) oil. Use of the incorrect oil can result in compressor failure.
  2. When replacing the A/C compressor, balance the compressor oil. Refer to Air Conditioning Compressor Oil Balancing
  3. Using J 39400 , leak test A/C compressor fittings.

Special Tools

J 39400 Electronic Halogen Leak Detector