GM Service Manual Online
For 1990-2009 cars only

Special Tools

    • J 41476 Front and Rear Cover Alignment Tool
    • J 41479-2A Crankshaft Rear Oil Seal Installation Guide
    • J 41480 Front and Rear Cover Alignment

    Object Number: 1977797  Size: SH

    Note: 

       • Do not use the crankshaft rear oil seal or the engine rear housing gasket again.
       • Do not apply any type of sealant to the rear housing gasket, unless specified.
       • The special tool in this procedure is used to properly align the engine rear housing at the oil pan surface.
       • Current design rear housings have alignment tabs for horizontal alignment. J 41476 tool is not required for proper alignment of current design rear housings. The housing may be installed and aligned with or without the seal already installed into the housing.

  1. Inspect the rear housing to identify for alignment tabs (1).

  2. Object Number: 63228  Size: MH
  3. Inspect the rear oil gallery plug for proper installation.

  4. Object Number: 1977798  Size: SH

    Note: The J 41479-2A guide is required when installing the rear housing with the rear oil seal. The J 41479-2A guide is used to guide and protect the rear seal sealing surface as it is installed over the rear flange of the crankshaft. The J 41479-2A guide is NOT required when installing the rear housing without rear oil seal.

  5. Install the J 41479-2A guide cone and bolts onto the rear of the crankshaft.
  6. Tighten the bolts until snug. Do not overtighten.
  7. Install the rear housing gasket (1), rear housing with seal (2), and bolts (3).
  8. Tighten the bolts finger tight. Do not overtighten.
  9. Remove the J 41479-2A guide and bolts.
  10. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 64204  Size: SH
  11. Install the J 41480 cover alignment and bolts.
  12. 8.1. Tighten the tool-to-engine block bolts to 25 N·m (18 lb ft).
    8.2. Tighten the J 41480 cover alignment tool-to-rear housing bolts evenly to 12 N·m (106 lb in).
    8.3. Tighten the rear housing-to-engine block bolts to 30 N·m (22 lb ft).
  13. Remove the J 41480 cover alignment and bolts.

  14. Object Number: 63240  Size: MH
  15. Measure the rear housing-to-engine block oil pan surface for flatness.
  16. 10.1. Place a straight edge onto the engine block and rear housing oil pan sealing surfaces.

    Avoid contact with the portion of the gasket that protrudes into the oil pan surface.

    10.2. Insert a feeler gage between the rear housing and the straight edge. The housing must be flush with the oil pan or no greater than 0.5 mm (0.02 in) below flush (a).
  17. If the rear housing-to-engine block oil pan surface alignment is not within specifications, repeat the housing alignment procedure.
  18. If the correct rear housing-to-engine block alignment at the oil pan surface cannot be obtained, replace the rear housing.