GM Service Manual Online
For 1990-2009 cars only

Special Tools

    • J 41479 Crankshaft Rear Oil Seal Installer
    • J 41479-2A Crankshaft Rear Oil Seal Installation Guide

    Object Number: 1699207  Size: SH

    Important: For proper orientation, note the installation direction of the oil seal. The oil seal is a reverse-lip design. The part number is applied to the outside face of the seal, as shown.

  1. Inspect the seal and identify the part number markings for proper orientation.
  2. Important: 

       • Do not lubricate the oil seal (1) inside diameter (ID) of the crankshaft surface.
       • Do not reuse the crankshaft rear oil seal (1).


    Object Number: 1950880  Size: SH
  3. Lubricate the outside diameter (OD) of the oil seal (1) with clean engine oil.
  4. DO NOT allow oil or other lubricants to contact the seal surface.

  5. Lubricate the rear cover (2) oil seal bore with clean engine oil.
  6. DO NOT allow oil or other lubricants to contact the crankshaft surface.


    Object Number: 1950877  Size: SH
  7. Install the J 41479-2A  (2) cone and bolts onto the rear of the crankshaft.
  8. Important:  Do not over tighten the bolts.

  9. Tighten the bolts.
  10. Install the rear oil seal (1) onto the J 41479  (3) and push the seal to the rear cover bore (2).
  11. Thread the J 41479  (3) threaded rod into the tapered cone until the J 41479  (3) contacts the rear oil seal (1).
  12. Align the rear oil seal (1) onto the J 41479  (3).
  13. Rotate the handle of the J 41479  (3) clockwise until the rear oil seal (1) enters and bottoms into the rear cover bore (2).
  14. Remove the J 41479  (3) and J 41479-2A .