GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 3289-20 Holding Fixture
    • J 23907 Slide Hammer with Bearing Adapter
    • J 26941 Bushing and Bearing Remover (3-4 inch)
    • J 36513 Gear and Bearing Separator Plate
    •  J 44707 T Bar Push Puller
    • J 44737 Shift Rail Bearing Remover
    •  J 44759 Adapter 3/8 NC to 5/8 NF
    • J 45358 Case Spreader
    • J 45380 Transfer Case Rear Bushing Remover and Installer
    • J 45759 Assembly Fixture

    Object Number: 860417  Size: SH
  1. If available, using the adapter studs, attach the J 45759  (2) to the transfer case.
  2. Mount the J 3289-20  (1) to a sturdy workbench.
  3. Install the J 45759  (2) into the J 3289-20  (1) and secure with the pivot pin.

  4. Object Number: 765905  Size: SH
  5. Remove the drain plug.
  6. Tip the transfer case to remove any remaining transfer case fluid.
  7. Notice: Refer to Transfer Case Seal Removal Notice in the Preface section.


    Object Number: 749056  Size: SH
  8. Using a fine flat-bladed screwdriver and a mallet, loosen the front input shaft seal.

  9. Object Number: 749057  Size: SH
  10. Using a small block of wood and a large flat-bladed screwdriver, remove the front input shaft seal from the transfer case.

  11. Object Number: 748967  Size: SH
  12. Remove the front input shaft seal.

  13. Object Number: 765907  Size: SH
  14. Remove the dust seal from the front output shaft. The front output shaft oil seal does not require removal at this time.

  15. Object Number: 743564  Size: SH
  16. Remove the transfer case bolt that is retaining the wiring harness bracket.
  17. Mark the location of the wiring harness bracket bolt.
  18. Remove the encoder/motor mounting bolts.

  19. Object Number: 743566  Size: SH
  20. Remove the encoder/motor assembly.

  21. Object Number: 765845  Size: SH
  22. Remove both vehicle speed sensors (VSS) and O-ring seals from the rear extension.
  23. Notice: Refer to Transfer Case Seal Removal Notice in the Preface section.


    Object Number: 765850  Size: SH
  24. Remove the rear output seal.

  25. Object Number: 1225128  Size: SH
  26. Inspect the rear output shaft bushing for scoring or wear.
  27. Remove the rear output shaft bushing using the J 45380 .
  28. • Install the finger section of the J 45380 in front of the bushing.
    • Install the tube and forcing screw assembly to the finger section. Ensure the forcing screw is backed out.
    • Using a wrench on the forcing screw, remove the rear output shaft bushing.

    Object Number: 743567  Size: SH

    Important: Remove the rear extension and case half bolts at the same time for easier rear case disassembly.

  29. Remove the rear extension mounting bolts.

  30. Object Number: 743568  Size: SH
  31. Remove the case half bolts.
  32. Notice: Refer to Machined Surface Damage Notice in the Preface section.


    Object Number: 748970  Size: SH
  33. Install the J 45358 between the tabs on one side of the case.
  34. Important: 

       • Ensure that all of the case half bolts have been removed.
       • DO NOT use screwdrivers or pry bars to separate the transfer case halves. The special tool must be used to separate the transfer case halves properly.

  35. Using the J 45358 , shear the sealer securing the front and rear case half together.
  36. Move the J 45358 to the tabs on the other side of the case and shear the sealer.

  37. Object Number: 748971  Size: SH
  38. Use a suitable prying tool at one side of the case half.

  39. Object Number: 748972  Size: SH
  40. Use a suitable prying tool at the other side of the cased halves.
  41. Working both tools, separate the front output shaft from the front output shaft bearing, and the input shaft from the output shaft.

  42. Object Number: 860418  Size: SH
  43. Remove the front case half from the rear case half. Only the input gear assembly will remain with the front case half.

  44. Object Number: 743574  Size: SH

    Important: If using the drive chain and sprockets again, mark the position of the drive chain to the sprockets in order for the proper wear pattern alignment.

  45. Remove the front output shaft from the front output shaft rear bearing.
  46. Remove the drive chain assembly from the drive gear on the output shaft and the driven gear on the front output shaft.

  47. Object Number: 743577  Size: SH
  48. Remove the retaining ring for the high/low shift fork.

  49. Object Number: 743579  Size: SH
  50. Remove the top shift fork spring.

  51. Object Number: 743581  Size: SH
  52. Remove the shift fork assembly from the shift fork shaft.

  53. Object Number: 748973  Size: SH
  54. Separate the shift fork from the range sleeve.

  55. Object Number: 743582  Size: SH
  56. Remove the bottom shift fork spring.

  57. Object Number: 743583  Size: SH
  58. Insert a screwdriver in the slot of the rear extension.

  59. Object Number: 743584  Size: SH
  60. Remove the rear extension from the rear case half.

  61. Object Number: 743585  Size: SH
  62. Using the J 44707  (1), the J 44759  (2), and the J 36513  (3), remove the speed sensor reluctor wheel from the rear output shaft.
  63. Discard the speed sensor reluctor wheel after removal.

  64. Object Number: 743587  Size: SH
  65. Remove the rear output shaft assembly.

  66. Object Number: 743588  Size: SH
  67. Remove the clutch lever from the rear case half.

  68. Object Number: 743589  Size: SH
  69. Remove the shift fork shaft with the shift detent lever. Rotate the control actuator lever shaft in order to remove the shift detent lever.

  70. Object Number: 743593  Size: SH
  71. Remove the oil pump cover mounting bolts.

  72. Object Number: 743615  Size: SH
  73. Remove the oil pump cover.

  74. Object Number: 743616  Size: SH
  75. Remove the oil pump drive gear, the inner rotor.
  76. Remove the oil pump driven gear, the outer rotor.

  77. Object Number: 743617  Size: SH
  78. While pushing down on the clutch apply plate, remove the clutch pressure plate bearing retaining ring.

  79. Object Number: 743623  Size: SH
  80. Remove the clutch inner plate.

  81. Object Number: 743627  Size: SH
  82. Remove the clutch pressure plate bearing.

  83. Object Number: 743633  Size: SH
  84. Remove the clutch apply plate.

  85. Object Number: 743638  Size: SH
  86. Remove the clutch spring.

  87. Object Number: 743643  Size: SH
  88. Remove the clutch hub retaining ring.

  89. Object Number: 743648  Size: SH
  90. Remove the clutch housing assembly.

  91. Object Number: 743650  Size: SH
  92. Hold on to the clutch plates, and turn the clutch housing over on a workbench.
  93. Remove the clutch housing from the clutch plates and the clutch hub.
  94. Remove the clutch hub from the clutch plates.

  95. Object Number: 765909  Size: SH
  96. Remove the drive sprocket retaining ring from the clutch housing.

  97. Object Number: 765913  Size: SH
  98. Remove the drive sprocket from the clutch housing.

  99. Object Number: 743652  Size: SH
  100. Remove the clutch housing retaining ring from the rear output shaft.

  101. Object Number: 743653  Size: SH
  102. Remove the rear output shaft rear thrust washer.

  103. Object Number: 743657  Size: SH
  104. Using a press, remove the planetary gear assembly.
  105. 59.1. Support the front case half on press plates, to allow the planetary gear assembly removal.
    59.2. Use a suitable adapter to press on the input gear bearing.

    Object Number: 743658  Size: SH
  106. Using a press, remove the input gear bearing.
  107. 60.1. Support the planetary gear assembly on press plates, to allow removal of the input gear.
    60.2. Use a suitable adapter to press on the input gear.

    Object Number: 743659  Size: SH
  108. Remove the input gear.

  109. Object Number: 743661  Size: SH
  110. Remove the planetary gear large diameter thrust washer.

  111. Object Number: 743660  Size: SH
  112. Remove the input gear smaller diameter thrust washer.

  113. Object Number: 765915  Size: SH
  114. If necessary, remove the bore seal and the input gear thrust bearing from the input gear.

  115. Object Number: 765919  Size: SH
  116. Remove the driven gear retaining ring from the front output shaft.
  117. Remove the driven gear from the front output shaft.

  118. Object Number: 765925  Size: SH
  119. Using a hydraulic press and a suitable adapter on the front input shaft, remove the front speed sensor reluctor wheel.

  120. Object Number: 765873  Size: SH

    Important:  The vent only requires removal if it is damaged.

  121. Remove the vent.

  122. Object Number: 765878  Size: SH
  123. Remove the front output shaft VSS and O-ring seal from the rear case.

  124. Object Number: 765882  Size: SH
  125. Remove the chip collector magnet from the rear case.

  126. Object Number: 743590  Size: SH
  127. Remove the oil pump suction pipe with the oil pump screen.

  128. Object Number: 765885  Size: SH
  129. Remove the retaining ring for the control actuator lever shaft.
  130. Discard the retaining ring.

  131. Object Number: 765887  Size: SH
  132. Remove the control actuator lever shaft from the rear case.

  133. Object Number: 765889  Size: SH

    Important: Only remove the bearings if they are faulty. Do not use the bearings again.

  134. Inspect the front output shaft rear bearing for being faulty. Refer to Transfer Case Cleaning and Inspection.
  135. Using the J 23907  (1) and the J 26941  (2), remove the rear bearing for the front output shaft.

  136. Object Number: 765892  Size: SH

    Important: Only remove the bearings if they are faulty. Do not use the bearings again.

  137. Inspect the rear output shaft bearing for being faulty. Refer to Transfer Case Cleaning and Inspection.
  138. Important: The bushing surface for the oil pump is located by the output shaft bearing. When using the J 26941 , the jaws must not come in contact with the oil pump bushing surface.

  139. Using the J 23907  (1) and the J 26941  (2), remove the rear output shaft bearing from the rear case. Ensure the jaws on the J 26941 are between the bearing and the oil pump bushing.

  140. Object Number: 765895  Size: SH

    Important: Only remove the bearings if they are faulty. Do not use the bearings again.

  141. Inspect the control actuator lever shaft bearing for being faulty. Refer to Transfer Case Cleaning and Inspection.
  142. Using the J 44707  (2) and the J 44737  (1), remove the control actuator lever shaft bearing.
  143. Notice: Refer to Transfer Case Seal Removal Notice in the Preface section.


    Object Number: 765899  Size: SH
  144. Using a suitable prying tool, remove the front output shaft seal.
  145. Discard the seal.

  146. Object Number: 765902  Size: SH

    Important: Only remove the bearings if they are faulty. Do not use the bearings again.

  147. Inspect the front output shaft front bearing for being faulty. Refer to Transfer Case Cleaning and Inspection.
  148. Using a hammer and a punch, remove the front bearing for the front output shaft from the front case.
  149. Clean and inspect all the internal parts of the transfer case. Refer to Transfer Case Cleaning and Inspection.