GM Service Manual Online
For 1990-2009 cars only

Special Tools

    • EN-48853 Front Cover Alignment Tool
    • J 41480 Front and Rear Cover Alignment

Removal Procedure

  1. Remove the engine front cover. Refer to Engine Front Cover Replacement.
  2. Remove the engine oil pan. Refer to Oil Pan Replacement.

  3. Object Number: 1552545  Size: SH
  4. Remove the crankshaft oil deflector nuts (403).
  5. Remove the crankshaft oil deflector (425).

  6. Object Number: 1552488  Size: SH
  7. Remove the oil pump bolts.
  8. Note: Do not allow dirt or debris to enter the oil pump assembly. Cap ends, as necessary.

  9. Remove the oil pump (413).
  10. Clean and inspect the oil pump. Refer to Oil Pump Cleaning and Inspection.

Installation Procedure

Note: Inspect the engine block oil gallery passages. These surfaces must be clear and free of debris or restrictions.


    Object Number: 1552488  Size: SH
  1. Align the splines of the crankshaft sprocket and the oil pump drive gears, and install the oil pump (413).
  2. Install the oil pump onto the crankshaft sprocket until the pump housing contacts the face of the engine block.
  3. Install the oil pump bolts (411). Do not tighten the bolts at this time.

  4. Object Number: 1552559  Size: SH
  5. Align the oil pump surfaces (1) with the engine block surfaces (2). The oil pump must be aligned flush or no greater than 0.1 mm (0.04 in) below the engine block oil pan rail.
  6. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1552560  Size: SH
  7. Install the EN-48853 cover alignment and bolts to the engine block. Tighten the EN-48853 cover alignment bolts to 25 N·m (18 lb ft).
  8. Firmly push the oil pump until the pump surfaces contact the J 41480 cover alignment. Continue to retain the pump to the J 41480 cover alignment . Tighten the oil pump bolts to 25 N·m (18 lb ft).

  9. Object Number: 1552545  Size: SH
  10. Install the crankshaft oil deflector (425) and nuts (403). Install the deflector onto the engine with the word "Rear" at the back of the engine block. Tighten the crankshaft oil deflector nuts to 25 N·m (18 lb ft).
  11. Install the engine oil pan. Refer to Oil Pan Replacement.
  12. Install the engine front cover. Refer to Engine Front Cover Replacement.