GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Tools Required

J 8080 Crankshaft Main Bearing Remover/Installer

  1. Remove the spark plugs. Refer to Spark Plug Replacement in Engine Electrical.
  2. Remove the oil pan. Refer to Oil Pan Replacement .
  3. Remove the oil pump. Refer to Oil Pump Replacement .
  4. Check the crankshaft main bearing caps for location markings. Mark the caps if necessary. The caps must be returned to their original locations during assembly.

  5. Object Number: 39908  Size: SH
  6. Remove the crankshaft main bearing caps.

  7. Object Number: 5150  Size: SH
  8. Remove the lower crankshaft main bearing inserts from the crankshaft main bearing caps.

  9. Object Number: 5151  Size: SH
  10. Remove the upper crankshaft main bearing inserts.
  11. 7.1. Insert the J 8080 into the crankshaft oil hole.
    7.2. Rotate the crankshaft to "turn" the bearing insert out of the block.
  12. Clean and inspect the components. Repair and replace as necessary.

Installation Procedure

Tools Required

J 8080 Crankshaft Main Bearing Remover/Installer


    Object Number: 5151  Size: SH
  1. Install upper crankshaft main bearing inserts.
  2. 1.1. Insert the J 8080 into a crankshaft main bearing oil hole.
    1.2. Apply engine oil to the inserts of the proper size.
    1.3. Insert the plain end of the insert, without the bearing tang, between the crankshaft and the notched side of the block.
    1.4. Rotate the crankshaft to "roll" the insert into the block.
    1.5. Remove the tool.

    Object Number: 5152  Size: SH
  3. Install the lower crankshaft main bearing inserts to the crankshaft main bearing caps.
  4. 2.1. Make sure the inserts are of the proper size.
    2.2. Apply engine oil to the inserts.
  5. Adjust the crankshaft main bearing clearance. Refer to Engine Mechanical Specifications .
  6. 3.1. Support the crankshaft upward to remove any clearance from the upper bearing.
    3.2. Measure the total clearance between the lower bearing and the journal.
  7. Install the crankshaft main bearing caps (except the rear cap).
  8. Install the bolts to the block.
  9. Tighten
    Tighten the crankshaft main bearing cap bolts to 105 N·m (75 lb ft).

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  10. Apply engine oil to the bearing insert.
  11. Install the crankshaft rear main bearing cap.
  12. Install the crankshaft rear main bearing cap bolts.
  13. Tighten
    Tighten the bolts temporarily to 14 N·m (124 lb in).

  14. Inspect the crankshaft end play. Refer to Crankshaft and Bearings Clean and Inspect (Bearing Fit) .
  15. Install the oil pump. Refer to Oil Pump Replacement .
  16. Install the oil pan. Refer to Oil Pan Replacement .
  17. Install the spark plugs. Refer to Spark Plug Replacement in Engine Electrical.