Transfer Case Disassemble

Tools Required

• J 2619-01  Slide Hammer
• J 3289-20  Holding Fixture. See Special Tools .
• J 22912-01  Split Plate Bearing Puller
• J 23907  Slide Hammer with Bearing Adapter. See Special Tools .
• J 26941  Bushing and Bearing Remover - 3-4 inch. See Special Tools .
• J 45358  Case Spreader. See Special Tools .
• J 45548  Mainshaft Support Bushing/Bearing Remover. See Special Tools .
• J 45759  Assembly Fixture. See Special Tools .

Fig 1: Attaching J 45759 To Transfer Case
Courtesy of GENERAL MOTORS CORP.
1. Using the adapter studs, attach the J 45759  to the transfer case. All of the transfer case disassembly procedures can be performed with the case mounted to the J 45759  .
Fig 2: View Of Front Transfer Case Bench Mount
Courtesy of GENERAL MOTORS CORP.
2. Mount the J 3289-20  (1) to a sturdy work bench. See Special Tools .
3. Install the J 45759  (2) into J 3289-20  (1) and secure with pivot pin. See Special Tools .
Fig 3: Drain Plug & Fill Plug
Courtesy of GENERAL MOTORS CORP.
4. Remove the drain plug and the fill plug. Ensure all of the transfer case fluid is drained out of the transfer case.
Fig 4: Flat-Tipped Screw Driver In Inner Race
Courtesy of GENERAL MOTORS CORP.
NOTE: Refer to Transfer Case Seal Removal Notice .
IMPORTANT: The front output shaft seal is a two piece internal seal. The inner seal race is a force fit on the front output shaft.
5. Remove the front output shaft seal by inserting a flat-tipped screwdriver behind the inner race of the seal.
6. Pry the inner seal race forward.
Fig 5: Inner Part Of Seal From Outer Seal Body
Courtesy of GENERAL MOTORS CORP.
7. Using a small pry bar, move the inner seal race forward on the front output shaft.
8. Remove the inner seal race from the front output shaft.
Fig 6: Flat-Tipped Screw Driver In Space Between Outer Race Of Seal & Transfer Case
Courtesy of GENERAL MOTORS CORP.
9. Insert a flat-tipped screwdriver or a small pry bar between the outer lip of the front output shaft seal and the transfer case.
10. Remove the remaining part of the front output shaft seal from the transfer case.
Fig 7: Locating Encoder Motor Assembly
Courtesy of GENERAL MOTORS CORP.
11. Remove the encoder motor bracket bolt.
12. Remove the encoder motor mounting bolts.
13. Remove the encoder motor assembly.
Fig 8: View Of Vehicle Speed Sensor (VSS) & O-Ring Seal
Courtesy of GENERAL MOTORS CORP.
14. Remove the rear vehicle speed sensor (VSS) and the O-ring seal.
Fig 9: Rear Output Shaft Seal
Courtesy of GENERAL MOTORS CORP.
NOTE: Refer to Transfer Case Seal Removal Notice .
15. Remove the rear output shaft seal by prying it out with a flat-blade screwdriver.
16. Remove the shipping seal from the rear output shaft, if equipped.
Fig 10: Identifying Transfer Case Retaining Bolts
Courtesy of GENERAL MOTORS CORP.
17. Remove the transfer case retaining bolts and washers.

    Mark the location of the brackets.

Fig 11: Separating Case Halves Using J 45358
Courtesy of GENERAL MOTORS CORP.
NOTE: Refer to Machined Surface Damage Notice .
18. Using the J 45358  between the tabs on the case halves, shear the sealer that is holding the case halves together. See Special Tools .
19. Using pry bars at each side of the case, remove the case from the locating pins.
Fig 12: Rear Case Half
Courtesy of GENERAL MOTORS CORP.
20. Remove the rear case half from the front case half. The rear output shaft will come with the rear case half.
Fig 13: Identifying Shift Fork Shaft Spring
Courtesy of GENERAL MOTORS CORP.
21. Remove the shift fork shaft spring.
Fig 14: Rear Sun Gear
Courtesy of GENERAL MOTORS CORP.
22. Remove the rear sun gear.
Fig 15: Locating Rear Output Shaft Thrust Washer
Courtesy of GENERAL MOTORS CORP.
23. Remove the rear output shaft thrust washer.
Fig 16: Planetary Differential Assembly
Courtesy of GENERAL MOTORS CORP.
24. Remove the planetary differential assembly.
Fig 17: Front Sun Gear
Courtesy of GENERAL MOTORS CORP.
25. Remove the front sun gear.
Fig 18: Drive Chain & Sprockets
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: If the chain and sprockets are to be used again, mark the relationship of the chain to the sprockets in order to mark the wear patterns.
26. Remove the chain with the drive sprocket and driven sprocket.
Fig 19: Difference Between Older & Newer Design of Sprocket
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: There was a mid year production change in the design to the mainshaft and the drive sprocket. If the mainshaft or the drive sprocket is found faulty during inspection, it may require the replacement of both components. If the drive sprocket and the mainshaft are the older designs and either component requires replacement, both the mainshaft and drive sprocket must be replaced as a kit. The replacement components will only be the new design. If the mainshaft and the drive sprocket are the new design, the components can be replaced individually.
27. Inspect the drive sprocket to identify if it is the older design (1) or the newer design (2).

    There is only a slight difference to the drive sprocket on the rear surface. If the rear of the sprocket is almost flat, it is the old design (1). If the rear of the sprocket has a slight step of approximately 1 mm (0.039 in), it is the new design (2).

Fig 20: Drive Sprocket Thrust Washer
Courtesy of GENERAL MOTORS CORP.
28. Remove the drive sprocket thrust washer.
Fig 21: Identifying Lockup Shift Assembly & Lockup Mode Shift Fork
Courtesy of GENERAL MOTORS CORP.
29. Remove the lockup shift assembly and lockup mode shift fork.
Fig 22: Lockup Mode Shift Fork & Lockup Shift Assembly
Courtesy of GENERAL MOTORS CORP.
30. Remove the lockup mode shift fork from the lockup shift assembly.
Fig 23: Illustrating Lockup Shift Assembly Components
Courtesy of GENERAL MOTORS CORP.
31. If necessary, disassemble the lockup shift assembly.
    1. Remove the retainer ring from the sleeve.
    2. Remove the hub.
    3. Remove the spring.
Fig 24: Inner Lockup Hub
Courtesy of GENERAL MOTORS CORP.
32. Remove the inner lockup hub.
Fig 25: Identifying Magnet
Courtesy of GENERAL MOTORS CORP.
33. Remove the magnet.
Fig 26: Expanded View Of Oil Pump Assembly
Courtesy of GENERAL MOTORS CORP.
34. Remove the oil pump assembly with the hose and screen.
Fig 27: Locating Oil Pump Hose & Screen
Courtesy of GENERAL MOTORS CORP.
35. Disconnect the oil pump hose from the oil pump screen.
36. Disconnect the oil pump hose from the oil pump.
Fig 28: Shift Fork Shaft
Courtesy of GENERAL MOTORS CORP.
37. Remove the shift fork shaft.
Fig 29: Shift Detent Lever Assembly
Courtesy of GENERAL MOTORS CORP.
NOTE: In order to prevent component damage, properly remove and install the shift detent lever shaft assembly. When removing or installing the shift detent lever shaft assembly, keep the shaft straight and do not tilt. Tilting the shift detent lever shaft assembly in the transfer case housing will break the tip on the end of the shaft.
38. Remove the shift detent lever assembly.
    • Rotate the high/low shift fork roller from the shift detent lever assembly.
    • Lift straight up on the shift detent lever assembly.
Fig 30: Expanded View Of Shift Detent Lever Assembly
Courtesy of GENERAL MOTORS CORP.
39. If necessary, disassemble the shift detent lever assembly.
    1. Hold the shift detent lever assembly by one tab of the spring (3), in a vise.
    2. Rotate the other spring tab and slide the detent lever cam (1) off the shaft.
    3. Remove the sleeve (2).
    4. Push the shaft (4) out of the spring (3).
Fig 31: Identifying Mainshaft
Courtesy of GENERAL MOTORS CORP.
40. Remove the mainshaft.
Fig 32: High/Low Range Sleeve & High/Low Range Shift Fork
Courtesy of GENERAL MOTORS CORP.
41. Remove the high/low range sleeve with the high/low range shift fork.
Fig 33: Range Shift Fork Range Shift Sleeve
Courtesy of GENERAL MOTORS CORP.
42. Remove the range shift fork from the range shift sleeve.
Fig 34: Input Shaft Thrust Washer
Courtesy of GENERAL MOTORS CORP.
43. Remove the input shaft thrust washer.
Fig 35: High/Low Planetary Carrier
Courtesy of GENERAL MOTORS CORP.
44. Remove the high/low planetary carrier.
Fig 36: Inspecting Mainshaft Front Support Bearing
Courtesy of GENERAL MOTORS CORP.
45. Inspect the mainshaft front support bearing for being faulty. Refer to Cleaning and Inspection .
46. Using a brass drift and a hammer, remove the mainshaft front support bearing from the planetary carrier assembly.
Fig 37: Front Output Shaft Assembly
Courtesy of GENERAL MOTORS CORP.
47. Remove the front output shaft assembly.
Fig 38: Removing Cup Plug
Courtesy of GENERAL MOTORS CORP.
48. If the cup plug in the front output shaft is leaking, remove the plug using a brass drift.
Fig 39: Identifying Input Seal
Courtesy of GENERAL MOTORS CORP.
49. Using a hammer and a suitable punch, remove the input seal.
Fig 40: Removing Input Shaft Bearing
Courtesy of GENERAL MOTORS CORP.
50. Using a hammer and a brass drift, remove the input shaft bearing from the front case half.
Fig 41: Removing Front Output Shaft Bearing
Courtesy of GENERAL MOTORS CORP.
51. Using a brass drift, remove the front output shaft bearing from the front case half.
Fig 42: Locating Retaining Ring For Annulus Gear
Courtesy of GENERAL MOTORS CORP.
52. Remove the retaining ring for the annulus gear.
Fig 43: Annulus Gear & Front Case Half
Courtesy of GENERAL MOTORS CORP.
53. Remove the annulus gear from the front case half.
Fig 44: Vent & Front Case Half
Courtesy of GENERAL MOTORS CORP.
54. If necessary, remove the vent from the front case half.
Fig 45: Identifying Rear Output Shaft & Outer Retaining Ring
Courtesy of GENERAL MOTORS CORP.
55. Remove the rear output shaft from the rear case half.
    1. Spread the rear output shaft rear bearing outer retaining ring.
    2. Using a soft-face hammer, tap on the end of the rear output shaft.
Fig 46: Removing Speed Reluctor Wheel By Using Hydraulic Press & J 22912-01
Courtesy of GENERAL MOTORS CORP.
56. Using a hydraulic press and the J 22912-01  , remove the speed reluctor wheel.

    Do not use the speed reluctor wheel again.

Fig 47: Identifying Rear Output Shaft Bearing Retaining Ring
Courtesy of GENERAL MOTORS CORP.
57. Remove the retaining ring for the rear output shaft bearing.
Fig 48: Pressing Out Rear Output Shaft Bearing
Courtesy of GENERAL MOTORS CORP.
58. Using a hydraulic press, remove the rear output shaft bearing.
Fig 49: Removing Mainshaft Rear Support Bushing From Rear Output Shaft Using J 2619-01 & J 45548
Courtesy of GENERAL MOTORS CORP.
59. Inspect the mainshaft rear support bushing in the rear output shaft for being faulty. Refer to Cleaning and Inspection .
60. Using the J 2619-01  (1) and the J 45548  (2), remove the mainshaft rear support bushing from the rear output shaft. See Special Tools .
Fig 50: Identifying J 26941 & J 23907
Courtesy of GENERAL MOTORS CORP.
61. Using the J 26941  (1) and the J 23907  (2), remove the rear bearing for the front output shaft from the rear case. See Special Tools .
Fig 51: Seal For Shift Detent Lever Shaft
Courtesy of GENERAL MOTORS CORP.
62. Remove the seal for the shift detent lever shaft by prying it out from the case.