GM Service Manual Online
For 1990-2009 cars only

Crankshaft Removal Procedure

  1. Before removing the crankshaft, measure the crankshaft end play using the following procedure:
  2. 1.1. Reinstall the lower crankcase.
    1.2. Place a dial indicator at the crankshaft nose.
    1.3. Gently force the crankshaft to the extreme front and rear positions with a pry tool while monitoring the movement of the dial indicator.
    1.4. The crankshaft end play should not exceed 0.05-0.5 mm (0.002-0.020 in).
    1.5. If the specifications are exceeded, replace the thrust bearing.
    1.6. If a new thrust bearing does not bring the tolerances within specification, replace the crankshaft.
    1.7. Remove the lower crankcase.
  3. Locate or fabricate 2 V-blocks to support the crankshaft.

  4. Object Number: 947617  Size: SH
  5. Using 2 hands, lift the crankshaft straight up from the engine block.
  6. Place the crankshaft on the V-blocks in a secure place.

  7. Object Number: 947623  Size: SH
  8. If damaged, remove the crankshaft sprocket drive pin (1) from the nose of the crankshaft.

Crankshaft Bearing Removal Procedure

  1. Prepare a piece of cardboard, or equivalent, numbered 1-5 for bearing identification. Main bearing journals are numbered from the front of the engine.

  2. Object Number: 947631  Size: SH
  3. Remove the upper crankshaft bearing halves from the cylinder block. Note the position of the thrust bearing (1) at the number 3 journal.
  4. Place the upper main bearing halves on the cardboard in the correct positions. Note that the number 3 bearing is the thrust bearing.

  5. Object Number: 947640  Size: SH
  6. Remove the lower main bearing halves from the lower crankcase.
  7. Place the lower main bearing halves in the correct positions on the cardboard.