GM Service Manual Online
For 1990-2009 cars only

Removal Procedure


    Object Number: 396828  Size: SH
  1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Remove the transfer case shields. Refer to Transfer Case Shield Replacement .
  3. Remove the front propeller shaft. Refer to Front Propeller Shaft Replacement in Propeller Shaft.
  4. Remove the rear propeller shaft.
  5. • For vehicles equipped with the one piece propeller shaft, refer to One-Piece Propeller Shaft Replacement in Propeller Shaft.
    • For vehicles equipped with the two piece propeller shaft, refer to Two-Piece Propeller Shaft Replacement in Propeller Shaft.

    Object Number: 715660  Size: SH
  6. Remove the motor/encoder electrical connector.

  7. Object Number: 715667  Size: SH
  8. Remove the transfer case vent hose.

  9. Object Number: 647994  Size: SH
  10. Remove the transfer case electrical wiring harness.
  11. Important: Make sure that the transfer case is properly secured to the transmission jack.

  12. Support the transfer case with a suitable transmission jack.

  13. Object Number: 715663  Size: SH

    Important: When removing the NVG 246 transfer case from the transmission, it is not necessary to remove the transmission mount or the transfer case adapter in order to remove the transfer case.

  14. Remove the transfer case retaining nuts from the transfer case studs.

  15. Object Number: 715726  Size: SH
  16. Separate the transfer case from the transmission by moving it straight back toward the rear of the vehicle.
  17. Rotate the transfer case so that it is perpendicular to the transmission assembly.
  18. Lower the transfer case.

Installation Procedure


    Object Number: 715726  Size: SH
  1. Rotate the transfer case so that it is perpendicular to the transmission assembly.
  2. Raise the transfer case into position.
  3. Rotate the transfer case so that it is aligns with the transfer case adapter.
  4. Install the transfer case assembly.

  5. Object Number: 715663  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  6. Install the transfer case retaining nuts.
  7. Tighten
    Tighten the transfer case retaining nuts to 50 N·m (37 lb ft).


    Object Number: 715667  Size: SH
  8. Install the transfer case vent hose.

  9. Object Number: 647994  Size: SH
  10. Install the transfer case electrical wiring harness.

  11. Object Number: 715660  Size: SH
  12. Install the motor/encoder electrical connector.
  13. Install the front propeller shaft. Refer to Front Propeller Shaft Replacement in Propeller Shaft.
  14. Install the rear propeller shaft.
  15. • For vehicles equipped with the one piece propeller shaft, refer to One-Piece Propeller Shaft Replacement in Propeller Shaft.
    • For vehicles equipped with the two piece propeller shaft, refer to Two-Piece Propeller Shaft Replacement in Propeller Shaft.
  16. Check the transfer case fluid level. Refer to Transfer Case Fluid Replacement .

  17. Object Number: 396828  Size: SH
  18. Install the transfer case shield. Refer to Transfer Case Shield Replacement .
  19. Lower the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.