GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 22912-B Rear Pinion and Axle Bearing Remover
    • J 23907 Slide Hammer
    • J 36513 Split Plate
    • J 39442 Press Adapter
    • J 39443 Split Plate
    • J 39473 Mainshaft Bearing Installer
    • J 39594 Bearing Race Remover

Mainshaft


    Object Number: 1887569  Size: SH

    Important: Measure the 4th speed gear synchronizer wear gap before disassembling the mainshaft.

  1. Install the input shaft in the adapter plate.
  2. Install the mainshaft on the input shaft.
  3. Using a feeler gauge measure the gap between the 4th speed gear blocking ring and the 4th speed gear.
  4. Replace the 4th speed gear friction cone and blocking ring when the gap is less than 1.27 mm (0.050 in).
  5. Notice: Do not overtighten the J 36513 split plate past the gear teeth or damage to gear may occur.

  6. Using the J 36513 , close the split plate only enough to support the gear teeth, and the J 39442 , remove the following parts in order:
  7. 5.1. The 6th speed driven gear
    5.2. The mainshaft large tapered bearing
    5.3. The 1st speed gear
    5.4. The 1st speed gear caged needle bearing
    5.5. The 1st speed locking ring
    5.6. The 1st speed 2 piece thrust washer

    Object Number: 1938370  Size: SH
  8. Remove the following parts in order:
  9. 6.1. The 1st speed gear inner cone
    6.2. The 1st speed gear friction cone
    6.3. The 1st speed gear blocking ring

    Object Number: 4810  Size: SH

    Important: The synchronizer hubs and sliding sleeves are a selected assembly. Keep these parts together as originally assembled.

  10. Scribe a mark on the synchronizer hub and on the sleeve. This will help you to reinstall the parts in the same position.

  11. Object Number: 1938374  Size: SH
  12. Remove the 2nd speed gear. The 1st/2nd speed synchronizer assembly, the 2nd speed gear blocking ring, the 2nd speed gear friction cone, and the 2nd speed gear inner cone will press off with the 2nd speed gear. Use the J 36513 in an inverted position, J 39442 and a hydraulic press.

  13. Object Number: 1938379  Size: SH
  14. Remove the 2nd speed gear spacer and caged needle bearing.

  15. Object Number: 38328  Size: SH
  16. Remove the mainshaft small tapered bearing. Use the J 39442 , the J 39443 , and a hydraulic press.
  17. Discard the small tapered bearing.

  18. Object Number: 1938384  Size: SH
  19. Remove the 3rd/4th synchronizer retaining ring.

  20. Object Number: 4810  Size: SH

    Important: The synchronizer hubs and sliding sleeves are a selected assembly. Keep these parts together as originally assembled.

  21. Scribe a mark on the synchronizer hub and on the sleeve. This will help you to reinstall the parts in the same position.

  22. Object Number: 1938387  Size: SH
  23. Use the J 39473 , V-blocks, and a hydraulic press to remove the following components:
  24. • 3rd/4th speed synchronizer assembly
    • 3rd speed gear blocking ring
    • 3rd speed gear friction cone
    • 3rd speed gear inner cone
    • 3rd speed gear

    Object Number: 1938390  Size: SH
  25. Remove the spacer.
  26. Remove the 3rd speed gear caged needle bearing.

Input Shaft


    Object Number: 1887570  Size: SH

    Important: Do not replace the tapered bearing or the bearing race unless inspection shows that the bearing or the race are damaged.

  1. Remove the tapered bearing from the input shaft, using the J 22912-B and a hydraulic press.

  2. Object Number: 1887571  Size: SH
  3. Remove the bearing race from the input shaft, using the J 23907  (1) and the J 39594  (2).