GM Service Manual Online
For 1990-2009 cars only

Special Tools

    • EN 46109 Guide Pins
    • J 39946 Crankshaft Socket - 4.0L and 4.6L
    • J 45059 Angle Meter

For equivalent regional tools, refer to Special Tools.


    Object Number: 1373496  Size: SH
  1. Place a 5 mm (0.197 in) spot of RTV sealant GM P/N 12378521 or equivalent (1) at the two points where the crankshaft rear oil seal meets the split line of the engine block.

  2. Object Number: 1373497  Size: SH

    Note: Ensure components being sealed with RTV are assembled within 20 minutes. Components assembled after the RTV has skinned-over, approximately 20 minutes, will not seal properly.

  3. Completely fill and slightly overfill the engine block seal groove with a continuous bead of RTV sealant GM P/N 12378521 or equivalent.
  4. Ensure the RTV sealant GM P/N 12378521 or equivalent bead is higher then the rail surface (1) by 3 mm (0.118 in).

  5. Object Number: 1373498  Size: SH
  6. Using a suitable tool spread the sealant in the area near the oil drain back passages (1) away from the oil drain back passages toward the outboard edge of the rail surface.

  7. Object Number: 1373499  Size: SH
  8. To prevent shifting of the lower crankcase install one of the EN 46109 pins into a bolt hole in each rail.

  9. Object Number: 1373506  Size: SH
  10. Install the cleaned lower crankcase onto the engine.

  11. Object Number: 1373509  Size: SH
  12. Using a rubber mallet gently tap the lower crankcase into position.
  13. Remove both of the EN 46109 pins .

  14. Object Number: 204167  Size: SH
  15. Loosely install the crankcase perimeter bolts on the right side.

  16. Object Number: 880592  Size: SH
  17. Loosely install the crankcase perimeter bolts on the left side.

  18. Object Number: 1373512  Size: SH
  19. Using a small long blade screwdriver clean out any sealant in the oil drain back passages (1).

  20. Object Number: 1650749  Size: SH

    Note: Ensure components being sealed with RTV are assembled within 20 minutes. Components assembled after the RTV has skinned-over, approximately 20 minutes, will not seal properly.

  21. Using a NEW oil distribution plate place a continuous 3 mm (0.118 in) wide bead of RTV sealant GM P/N 12378521 or equivalent on top of the outer seal (1) of the oil distribution plate place.

  22. Object Number: 1373514  Size: SH
  23. To prevent shifting of the oil distribution plate install one of the EN 46109 pins into a bolt hole in each side of the lower crankcase.

  24. Object Number: 1373515  Size: SH
  25. Install the NEW oil distribution plate.
  26. Remove both of the EN 46109 pins .
  27. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1373517  Size: SH
  28. Install the oil distribution plate bolts and tighten to 10 N·m (89 lb in).

  29. Object Number: 1373518  Size: SH
  30. Using a small long blade screwdriver clean out any sealant in the oil drain back passages.

  31. Object Number: 204586  Size: SH
  32. Install the crankshaft oil scraper plate.
  33. Install the main bearing bolts. Ensure the stud-head bolt (1) used for the oil suction tube support bracket is placed in the proper position.

  34. Object Number: 639603  Size: SH
  35. Tighten the main bearing bolts in the proper sequence.
  36. 20.1. Tighten the main bearing bolts (1-20) to 20 N·m (15 lb ft ) in the proper sequence.
    20.2. Tighten the main bearing bolts (1-20) an additional 65 degrees in the proper sequence using the J 45059 meter .

    Object Number: 639604  Size: SH
  37. Tighten the crankcase perimeter bolts in sequence shown. Tighten the crankcase perimeter bolts to 30 N·m (22 lb ft).

  38. Object Number: 1373521  Size: SH
  39. Using a small long blade screwdriver verify that the threaded holes for the oil pan bolts and the oil drain back passages are clear of sealant.
  40. Using the J 39946 socket rotate the crankshaft until the number one piston is at top dead center (TDC) and the crankshaft key way is approximately at the 7 o'clock position.