GM Service Manual Online
For 1990-2009 cars only

Differential Housing

    Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 777581  Size: SH
  1. Clean the differential housing in solvent.
  2. Clean and inspect the differential housing for the following:
  3. • The mounting bolt threads (3)
    • The case cover bolt hole threads (4)
    • The O-ring sealing surface for nicks or burrs (5)
    • The drain plug hole threads (6)
    • The axle seal area (2)
    • The pinion bolt hole threads (7)
    • The bushing bore (1)
    • Cracks in the housing, if removed

    Object Number: 777584  Size: SH
  4. Clean the oil passage between (1) and (2), in the axle bearing bore.

  5. Object Number: 777586  Size: SH
  6. Clean the oil passage between (1) and (2), in the pinion carrier bore.
  7. In 2 locations (3) inspect the pinion housing surface.

Differential Carrier Cover

    Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 777589  Size: SH
  1. Clean the differential carrier cover in solvent.
  2. Clean and inspect the differential carrier cover for the following:
  3. • Clean the oil passage between (1) and (2), in the axle bearing bore.
    • Inspect the cover flat (3) for nicks and burrs.
    • Clean the fill plug hole threads (4).
    • Clean the O-ring groove (5).
    • Inspect the race and shim surfaces (6) and (7).

    Object Number: 777592  Size: SH
  4. Inspect the differential carrier cover exterior for the following:
  5. • The vent for proper operation (1)
    • The mounting bolt threads (2)
    • The axle seal mounting surface (3)

Drive Planetary Gear Carrier

    Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 777594  Size: SH
  1. Clean the drive pinion carrier housing in solvent.
  2. Clean and inspect the drive pinion carrier housing for the following:
  3. • Clean the oil passages between holes (1) and (2) and between holes (5) and (6).
    • Inspect the pinion seal area (3) and the bearing races (4, 7) for damage.

    Object Number: 777597  Size: SH
  4. Clean and inspect the following:
  5. • The O-ring groove (2) for nicks and burrs
    • The flat surface (3) for nicks
    • The races (1)