GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Tools Required

    • J 5239 Connecting Rod Bolt Guide Set
    • J 24270 Cylinder Bore Ridge Reamer
  1. Remove the cylinder head(s). Refer to Cylinder Head Replacement and/or Cylinder Head Replacement .
  2. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Remove the oil pan. Refer to Oil Pan Replacement .
  4. Remove the oil pump. Refer to Oil Pump Removal .
  5. Remove the crankshaft oil deflector. Refer to Crankshaft Oil Deflector Replacement .
  6. Rotate the crankshaft until the piston and rod assembly to be serviced is at Bottom Dead Center (BDC).

  7. Object Number: 11497  Size: SH
  8. Mark the piston with the number of the cylinder from which the piston is being removed.
  9. Mark the connecting rod and the connecting rod cap in order to ensure correct assembly.
  10. Notice: If there is a pronounced ridge at the top of the piston travel, the ridge must be removed with a ridge reamer before the piston and connecting rod assembly are removed. Applying force may break the piston rings or damage the piston.

  11. Use the J 24270
  12. Complete the following steps:

    9.1. Turn the crankshaft until the piston is at the bottom of the stroke.
    9.2. Cover the piston with a cloth.
    9.3. Remove the cylinder ring ridge.
    9.4. Turn the crankshaft until the piston is at the top of the stroke.
    9.5. Remove the cloth.
    9.6. Remove the metal shavings from the cylinder and piston.

    Object Number: 60874  Size: SH
  13. Remove the connecting rod nuts and cap.
  14. Remove the connecting rod cap and bearing half.
  15. Notice: Install thread protector in order to avoid damage to the crankshaft journal.

  16. Remove the connecting rod and piston assembly. Push out the assembly using a suitable tool.
  17. Lower the vehicle.
  18. Inspect the piston. Refer to Piston, Connecting Rod, and Bearing Cleaning and Inspection .
  19. Inspect the connecting rod bearings. Refer to Piston, Connecting Rod, and Bearing Cleaning and Inspection .
  20. Inspect the connecting rod cap and connecting rod. Refer to Piston, Connecting Rod, and Bearing Cleaning and Inspection .
  21. Inspect the crankshaft connecting rod journal. Refer to Crankshaft and Bearing Cleaning and Inspection .
  22. Hone the cylinder bore.
  23. Clean the cylinder bores with hot water and detergent.
  24. Dry the cylinder bores with a clean, dry cloth.
  25. Use a clean dry cloth in order to swab the cylinder bores with NEW engine oil.

Installation Procedure

Tools Required

    • J 5239 Connecting Rod Guide.
    • J 8037 Piston Ring Compressor
    • J 36660-A Torque Angle Meter

    Object Number: 31373  Size: SH
  1. Lubricate the cylinder wall and piston rings with clean engine oil.
  2. Turn the crankshaft to bottom dead center.
  3. Install the J 5239 .

  4. Object Number: 43397  Size: SH
  5. Install the J 8037 .
  6. Install the piston and connecting rod assembly.
  7. Important: Ensure that the arrow on top of the piston or the markings made during removal face towards the front of the engine, or are in the same location as when removed.

  8. Remove the thread protectors.
  9. Notice: In order to prevent the possibility of rod bolt or bearing cap damage, the bearing caps may need to be tapped into position with a brass or leather mallet before the attaching nuts are installed. Do not use the attaching nuts to pull the bearing caps onto the rod. Failure to observe this information may result in damage to the rod bolt or the bearing cap.

  10. Perform one of the following items in order to seat the connecting rod bearing caps:
  11. • Push on the bearing by hand.
    • Carefully, lightly tap the bearing caps using a suitable tool.

    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.

  12. Install the connecting rod bearing cap nuts.
  13. Tighten
    Tighten the connecting rod bearing cap nuts to 20 N·m (15 lb ft). Use the J 36660-A in order to rotate the nuts an additional 75 degrees.

  14. Pry the connecting rod back and forth using a suitable tool. Inspect for binding. Loosen and retighten the bearing cap, as needed.

  15. Object Number: 35206  Size: SH
  16. Measure the connecting rod side clearance.
  17. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  18. Install the crankshaft oil deflector. Refer to Crankshaft Oil Deflector Replacement .
  19. Install the oil pump. Refer to Oil Pump Installation .
  20. Install the oil pan. Refer to Oil Pan Replacement .
  21. Lower the vehicle.
  22. Install the cylinder head(s). Refer to Cylinder Head Replacement and/or Cylinder Head Replacement .