GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2008 🢒 G8 🢒 Preface 🢒 Cautions and Notices 🢒 Differential Oil Replacement

Draining Procedure

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

    Caution: Refer to Vehicle Lifting Caution in the Preface section.

  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  2. Place a large suitable container under the differential in order to collect draining differential fluid.

    3. Object Number: 1958883 Size: SH

    Important: Clean the area around the differential plug (1) to prevent the entry of foreign particles into the differential (2).

    Important: The differential fill plug (1) and O-ring (3) come as an assembly, the O-ring (3) cannot be replaced separately.

  3. Remove the differential fill plug (1) from the differential (2).
  4. Inspect the differential fill plug (1) and O-ring (3) for excessive wear and/or damage. Replace as necessary.

    5. Object Number: 1958885 Size: SH

    Important: Clean the area around the differential plug (1) to prevent the entry of foreign particles into the differential (2).

    Important: The differential drain plug (1) and O-ring (3) come as an assembly, the O-ring (3) cannot be replaced separately.

  5. Remove the differential drain plug (1) from the differential (2).
  6. Inspect the differential drain plug (1) and O-ring (3) for excessive wear and/or damage. Replace as necessary.
  7. Allow the differential fluid to drain completely.

Filling Procedure

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1958885 Size: SH
  1. Install the differential drain plug (1) and O-ring (3) to the differential (2).

    2. Tighten
    Tighten the differential drain plug to 35 N-m (26 lb ft).

    Important: When adding fluid or making a complete fluid change, always use the correct differential fluid. Failure to use the correct fluid may cause gear damage and/or fluid leaks. For fluid specifications refer to Lubrication Specifications .

    Important: The differential fluid level must be level with the bottom of the fill plug hole to no lower than 6 mm (0.25 in) below the opening.

  2. Fill the differential to the correct level.

    3. Object Number: 1958883 Size: SH
  3. Install the differential fill plug (1) and O-ring (3) to the differential (2).

    4. Tighten
    Tighten the differential fill plug to 35 N-m (26 lb ft).

  4. Remove safety stands.
  5. Lower the vehicle to the ground.