GM Service Manual Online
For 1990-2009 cars only

Piston and Piston Pin


    Object Number: 1801670  Size: SH

    Important: The arrow located on top of the piston must point toward the front of the engine.

    Important: The connecting rod is non-directional and may be assembled/reassembled to the piston in either direction.

  1. Lubricate the piston pin (1) bores in the piston (2) and the connecting rod with clean engine oil.
  2. Assemble the piston and piston pin to the connecting rod. Correctly orient the piston when reusing a marked connecting rod.
  3. Align the piston pin bore with the connecting rod pin bore.
  4. Slide the piston pin into the piston and the connecting rod.

  5. Object Number: 1801668  Size: SH

    Important: New piston pin retainers must be used. Never reuse the piston pin retainers.

  6. Install new piston pin retainers (1).
  7. Ensure the piston pin retainers are fully seated in their grooves.
  8. Repeat steps 1 to 6 for the remaining pistons.

Piston Ring


    Object Number: 1801706  Size: SH
  1. Correctly orient the oil control ring expander (1) before installation. The ends of the expander must be facing toward the top of the piston.

  2. Object Number: 1801711  Size: SH
  3. Using a piston ring expander, install the oil control ring assembly using the following procedure:
  4. 2.1. Install the expander ring (3).
    2.2. Install the two oil scraper rings (4). Expand the rings only enough to clear the piston diameter. Over-expanding the piston rings will distort or crack the rings.

    Object Number: 1801667  Size: SH
  5. Using the ring expander (1), install the second piston ring (2) onto the piston (3). Do not over-expand the ring. Repeat for the top ring.

  6. Object Number: 1801714  Size: SH
  7. Once the rings are installed, set the ring gaps for the oil control, second and top ring as follows. Use the piston location arrow for reference.
  8. • Lower oil control ring position (1).
    • Upper oil control ring position (2).
    • Top ring position (3).
    • Oil control ring expander position (4).
    • Second ring position (5).

Connecting Rod Bearing


    Object Number: 1801723  Size: SH

    Important: If the connecting rod bearings have been used in a running engine, they must be replaced with new connecting rod bearings for reassembly.

  1. Clean the connecting rod (2) and the connecting rod cap bearing bore with a lint-free cloth.
  2. Clean the oil from behind the connecting rod bearing halves.
  3. Install a new upper connecting rod bearing (1) into position. Roll the bearing into position so the lock tang engages the alignment slot. The bearing must fit flush in the connecting rod.

  4. Object Number: 1801658  Size: SH
  5. Install the lower connecting rod bearing (1) into position in the connecting rod cap (2).
  6. Roll the bearing into position so the lock tang engages the alignment slot. The bearing must fit flush with the connecting rod cap.