GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • DT-48008 Press Support/Pinion Bearing Installer
    • DT-48009-2 Gage Plate Assembly
    • DT-48009-3 Depth Gage
    • J 42155 Getrag Axle Differential Housing Lifting Tool
    • J 42168-1 Shim Measuring Tool
    • J 42168-2 Shim Measuring Tool
    • J 42168-9 Shim Measuring Tool
    • J 42168-11 Shim Measuring Tool
    • J 42168-15 Compressor Assembly
    • J 42168-16 Spacers
    • J 42170 Getrag Axle Bearing Race Installer
    • J-42173-A Differential Holding Fixture

    Object Number: 1491715  Size: SH
  1. Remove the J 42168-9  (1) and thumbscrew from the J 42168-1  (2).

  2. Object Number: 354433  Size: SH
  3. Remove the J 42168-1 from the left bearing cup bore of the differential housing.

  4. Object Number: 1654343  Size: SH

    Important: Level the tool in order to obtain accurate measurements.

  5. Install the DT-48009-2 into a vice.

  6. Object Number: 1654348  Size: SH
  7. Position the bearing cup (2) onto the DT-48009-2  (3).
  8. Use the J 42155 in order to position the differential case (1) onto the DT-48009-2  (3) and into the bearing cup (2). Rotate the differential, in both directions, in order to seat the bearing to the cup.

  9. Object Number: 1658454  Size: SH
  10. Install the DT-48009-3  (2) into the hole in J 42168-2  (1). Loosen the thumbscrew and allow the rod to contact the bottom of the bearing cup bore, machined surface (3).
  11. Tighten the thumbscrew.
  12. Remove the DT-48009-3 from the J 42168-2  (1).

  13. Object Number: 1654350  Size: SH
  14. Using a ring gear bolt, attach the DT-48009-3  (2) to the ring gear side of the differential (1).
  15. Rotate the differential until the rod of DT-48009-3  (2) is above the DT-48009-2  (3) gage block.

  16. Object Number: 1658464  Size: SH
  17. The DT-48009-2 upper gage block location (1) is used when servicing 2.56 and 2.93 ratio differentials.

  18. Object Number: 1654353  Size: SH
  19. Using a feeler gage, measure the distance between the rod of DT-48009-3  (1) and the gage block of DT-48009-2  (2). Record the measurement as dimension C1.
  20. Subtract C1 value from a C nominal value of 5 mm (0.197 in). Record that calculation as C2.
  21. Refer to the applicable calculation table in Spacer and Shim Specifications .


    Object Number: 1491721  Size: SH
  22. Locate the A2 value (2) on the side of the ring gear.
  23. Important: The A2 value is a manufacturing variation between the ring gear and pinion. The A2 value may be higher, lower, or equal to 74.5 mm (2.93 in), 2.93 ratio differential, nominal value. When subtracting the D nominal value from the A2 value, the C3 calculation may compute to a positive, negative, or zero total.

  24. Subtract the D nominal value of 74.5 mm (2.93 in) from the A2 value. Record the calculation as C3.
  25. Add the C2 value to the C3 value for the proper left side differential bearing shim thickness. The C3 value may be a positive, negative, or zero value.

  26. Object Number: 177407  Size: SH
  27. Select shims equal to the calculated value. It may be necessary to round the shim or shims total to obtain the proper shim sizes. If the shim thickness calculation is past the midpoint value, round the number to the next decimal value. Refer to Rear Axle Specifications .
  28. Remove the pinion housing/cage bolts (1).

  29. Object Number: 1041943  Size: SH
  30. Remove the pinion housing/cage (4) from the differential.

  31. Object Number: 354430  Size: SH
  32. Remove the J 42168-11 , bearings (3 and 6), spacer (5), and the J 42168-2  (7) from the pinion housing/cage (4).

  33. Object Number: 1654285  Size: SH

    Notice: Use the DT-48008 to support the differential housing in the press to prevent damage to the differential housing.

  34. Use the DT-48008  (4), the J 42170  (1) and a hydraulic press in order to install the selected shim (3) and bearing cup (2) to the differential housing.

  35. Object Number: 1491724  Size: SH
  36. Install the differential assembly (1) onto the J-42173-A  (2).
  37. 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.

  38. Install 4 M8 x 1.25 bolts (3).
  39. Tighten
    Tighten the bolts to 28 N·m (20 lb ft).


    Object Number: 1852864  Size: SH
  40. Install the ring gear (1) to the differential. Use several bolts to properly align the ring gear to the case.
  41. A hammer and brass punch may be used to aid in seating the ring gear onto the differential case.

    Important: Two types of ring gear bolts may be available for replacement. First design bolts (3) have serrations under the head and are torqued to 195 N·m (144 lb ft). The second design (4) are smooth under the head and are torqued to 145 N·m (107 lb ft).

  42. Install the NEW ring gear bolts (2).

  43. Object Number: 1041927  Size: SH
  44. Position the differential assembly onto the J-42173-A .
  45. Tighten
    Tighten the ring gear bolts to 195 N·m (144 lb ft) - 1st design.

    Tighten
    Tighten the ring gear bolts to 145 N·m (107 lb ft) - 2nd design.


    Object Number: 1041963  Size: SH
  46. Use the J 42155 in order to install the differential case into the differential housing.

  47. Object Number: 1041967  Size: SH
  48. Install the right side bearing cup (104), and the J 42168-15 onto the differential.

  49. Object Number: 1041970  Size: SH

    Important: In order to perform the shim selection procedure:

       • The oil seal must be removed from the right cover.
       • The pinion housing/cage must NOT be installed to the differential case.

  50. Install the right cover  (3) and J 42168-16 bolts (1) and spacers (2) to the differential. Position the J 42168-16 bolts and spacers evenly apart.
  51. Tighten
    Tighten the bolts to 28 N·m (20 lb ft).


    Object Number: 1041973  Size: SH
  52. Insert a feeler gage into the J 42168-15 and measure the gap. The measured dimension is the right side differential bearing shim size.

  53. Object Number: 1041970  Size: SH
  54. Remove the bolts (1), cover (3), and tools.

  55. Object Number: 1041772  Size: SH
  56. Install the selected shim (103) and bearing cup (104) to the right cover.

  57. Object Number: 1041975  Size: SH
  58. Using the J 42170 and a hydraulic press, install the shim or shims and bearing cup into the right cover . Refer to Rear Axle Assemble .