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Home >> Buick >> 2021 >> Envision Avenir, AWD >> Repair and Diagnosis >> Transmission >> Automatic Trans >> Power Transfer Unit/Transfer Case - AAM >> Repair Instructions - Off Vehicle >> Power Transfer Unit Case Disassemble >> Power Transfer Unit Case Disassemble
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Power Transfer Unit Case Disassemble

  1. GM5666686Courtesy of GENERAL MOTORS COMPANY
    NOTE:

    Always secure with the pivot pin after rotating.

    NOTE:

    The power transfer unit can be rotated 360 degrees to facilitate repair.

    Mount the power transfer unit case (3) to the DT-36842  Transaxle Holding Fixture (2) and then mount them to the DT-3289-20  Holding Fixture (1).

  2. GM5666056Courtesy of GENERAL MOTORS COMPANY
    NOTE:

    The plug and seal are only available as an assembly. Install a NEW plug with seal during assembly.

    Power Transfer Unit Fill Plug (1) - Remove and DISCARD

  3. NOTE:

    The plug and seal are only available as an assembly. Install a NEW plug with seal during assembly.

  4. Power Transfer Unit Drain Plug (2) - Remove and DISCARD
  5. NOTE:

    Remove the vent hose connector only if replacement is required.

  6. Power Transfer Unit Vent Hose Connector (3) - Remove and DISCARD
  7. GM5666054Courtesy of GENERAL MOTORS COMPANY

    Power Transfer Unit Half Shaft Retainer Clip (1) - Remove and DISCARD

  8. Power Transfer Unit Half Shaft Seal (2) - Remove and DISCARD
  9. NOTE:

    Push the OD flange of the seal to remove from extension housing and shaft.

  10. Power Transfer Unit Intermediate Drive Shaft to Input Shaft Seal (3) - Remove and DISCARD
  11. Power Transfer Unit Intermediate Drive Shaft Retainer (4) - Remove
  12. Power Transfer Unit Intermediate Drive Shaft (5) - Remove
  13. GM5605390Courtesy of GENERAL MOTORS COMPANY
    CAUTION:

    Do not nick, scratch or damage the sealing surface. The sealing surface is a machined surface. Damage to the machined surface can cause leakage.

    Power Transfer Unit Intermediate Drive Shaft Bearing Retaining Ring (1) - Remove

  14. NOTE:

    Use a press to remove the bearing from the power transfer unit intermediate drive shaft.

  15. Power Transfer Unit Intermediate Drive Shaft Bearing (2) - Remove
  16. Power Transfer Unit Intermediate Drive Shaft Bearing Retaining Ring (3) - Remove
  17. GM3793513Courtesy of GENERAL MOTORS COMPANY

    Power Transfer Unit Propeller Shaft Retainer (1) - Remove and DISCARD

  18. Power Transfer Unit Propeller Shaft Seal (2) - Remove and DISCARD
  19. NOTE:

    Use a screwdriver to remove the seal from the housing. Remove the inner part of the seal first and then the outer part of the seal. Use care to prevent damage to the housing seal bore or shaft sealing surface. The seal is to be removed in two pieces.

  20. Power Transfer Unit Output Shaft Seal (3) - Remove and DISCARD
  21. GM5666985Courtesy of GENERAL MOTORS COMPANY

    Power Transfer Unit Shift Actuator Bolt (1) - Remove [4x]

  22. Power Transfer Unit Shift Actuator (2) - Remove
  23. Power Transfer Unit Shift Actuator Seal (3) - Remove and DISCARD
  24. GM5666046Courtesy of GENERAL MOTORS COMPANY

    Power Transfer Unit Cover Housing Bolt (1) - Remove and DISCARD [10x]

  25. Power Transfer Unit Cover Housing (2) - Remove
  26. Power Transfer Unit Cover Housing Seal (3) - Remove and DISCARD
  27. GM3793530Courtesy of GENERAL MOTORS COMPANY

    Power Transfer Unit Input Shaft (1) - Remove

  28. Power Transfer Unit Idler Shaft (2) - Remove
  29. NOTE:

    The orientation of the tube for assembly. The end of the tube with the knurled OD area is to be facing the extension housing.

  30. Power Transfer Unit Idler Shaft Tube (3) - Remove
  31. GM5731409Courtesy of GENERAL MOTORS COMPANY

    Install the DT-45124-9  Puller Legs (2) to the DT-45124  Removal Bridge (1).

  32. GM3793536Courtesy of GENERAL MOTORS COMPANY

    Using the DT-26941  Bushing and Bearing Remover (4) and DT-45124  Removal Bridge (5), remove and discard the front power transfer unit input shaft seal (1).

  33. Power Transfer Unit Idler Gear Shaft Tube O-ring (2) - Remove and DISCARD
  34. NOTE:

    Remove as required.

  35. Power Transfer Unit Locating Pin (3) - Remove [2x]
  36. GM5830650Courtesy of GENERAL MOTORS COMPANY

    Power Transfer Unit Face Seal (1) - Remove and DISCARD

  37. GM3793539Courtesy of GENERAL MOTORS COMPANY

    Power Transfer Unit Idler Gear Shaft Tube O-ring (1) - Remove and DISCARD

  38. Using the DT-26941  Bushing and Bearing Remover (4) and DT-45124  Removal Bridge (3) remove and discard the rear power transfer unit input shaft seal (2).