GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 44755 Holding Fixture

Transfer Case Cleaning - Fiber Material from Transmission into Transfer Case


    Object Number: 746869  Size: SH

    Important: Transmission oil circulates between the transmission assembly and the transfer case differential carrier and three helical gear set. In situations where transmission related failures circulate fiber type debris, such as clutch friction disc material into the transfer case, the helical gear portion of the transfer case must be disassembled, cleaned and inspected for damage. In situations where transmission or transfer case related failures circulate metal type debris, such as bearing material, repair or overhaul of both components may be required.

  1. Install the transfer case assembly (1) onto the J 44755  (3). Position the carrier onto the post of the fixture.
  2. 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.

  3. Install the retaining bolts (2).
  4. Tighten
    Tighten the bolts to 50 N·m (37 lb ft).


    Object Number: 630579  Size: SH
  5. Remove the speed sensor (1).

  6. Object Number: 630591  Size: SH
  7. Remove the bolts (1) from the case.

  8. Object Number: 630592  Size: SH
  9. Separate the case-right (2) from the case-left (1).

  10. Object Number: 754871  Size: SH
  11. Clean the case-left and driveshaft gear (1) in solvent. Inspect for fiber or metal type debris within the unit and repair as required.

  12. Object Number: 630596  Size: SH
  13. Clean the case-right and idler gear (1) in solvent. Inspect for fiber or metal type debris within the unit and repair as required.
  14. Apply sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the sealing surface of the case-right.
  15. Install the idler gear (1) to the case-right.

  16. Object Number: 659130  Size: SH
  17. Install the idler gear into the case-right. The side of the gear with the long flange area (1) should be installed to the case-right.

  18. Object Number: 630592  Size: SH
  19. Install the case-right (2) to the case-left (1).

  20. Object Number: 630591  Size: SH
  21. Install the bolts (1) to the case.
  22. Tighten
    Tighten the bolts to 60 N·m (44 lb ft).


    Object Number: 630579  Size: SH
  23. Install the speed sensor (1) and O-ring.

Gears Cleaning and Inspection


    Object Number: 659131  Size: SH
  1. Inspect the idler gear (2) for wear, pitting, or discoloration by heat.

  2. Object Number: 630613  Size: SH
  3. Inspect the drive and drivenshafts for worn or damaged gears (1).

  4. Object Number: 630615  Size: SH
  5. Inspect the differential carrier and ring gear for the following:
  6. • Worn gears (1)
    • Damaged threads (2)
    • Scored, pitted, or damaged bearing (3)
    • Worn gear set or loose center pin (4)
    • Worn or loose gears (5)

    Object Number: 630604  Size: SH
  7. Inspect the gears (3) for abnormal wear.

Bearings and Shafts Cleaning and Inspection


    Object Number: 630608  Size: SH
  1. Inspect the flange sealing surface (1) for wear, damaged bolt threads (2) and worn or damaged splines (3).

  2. Object Number: 630613  Size: SH
  3. Inspect the drive and drivenshafts for the following:
  4. • Worn gear teeth (1)
    • Worn or scored driveshaft sealing surface (2)
    • Worn or damaged splines (3)
    • Damaged threads (4)
    • Pitted, scored, or damaged bearings (5)

    Object Number: 630604  Size: SH
  5. Inspect the differential carrier gear needle bearings (4 and 6) for wear. Inspect for a worn or scored pin (9).

  6. Object Number: 1465  Size: SH
  7. Inspect the bearing rollers and races for the following:
  8. • Pitting
    • Scoring or grooves
    • Excessive wear or other damage

    Object Number: 1458  Size: SH
  9. Inspect the bearing rollers and races for heat discoloration. Heat discoloration ranges from a faint yellow to a dark blue color. This discoloration may result from an overload or improper lubrication. Excessive heat causes softening of the rollers and races. Bearings or races with a sign of heat discoloration must be replaced.

  10. Object Number: 1648  Size: SH
  11. Inspect for a bent bearing cage.