GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1999 🢒 GMC K Pickup - 4WD 🢒 Engine 🢒 Engine Mechanical - 6.5L 🢒 Piston and Connecting Rod Assemble

Tools Required

J 39507 Piston Retaining Ring Installer


    Object Number: 59946 Size: SH
  1. Install the piston to the connecting rod.
    2. • Install the piston with the piston crown indent on the same side as the connecting rod bearing tang slots.
    • When installing the piston in the cylinder, the piston crown indent on the top of the piston must be towards the outside of the cylinder.

    Object Number: 66582 Size: SH
  2. Apply engine oil to the surface of the piston pin.
  3. Install the piston pin to the piston and the connecting rod.

    4. Important: Piston, piston pin, and connecting rod assembly must be stable (held firmly with no lateral movement) during piston pin retaining ring installation.

  4. Install the piston pin retaining rings, using theJ 39507 .
  5. Align the open end of the retaining ring toward the bottom of the piston.

    6. Object Number: 66581 Size: SH
  6. Use a small screwdriver and start one end of the ring in the groove.
  7. Install the J 39507 through the ring and into the piston pin.

    8. Object Number: 66580 Size: SH
  8. Press down on the ring with the pin on the tool.
  9. Turn the tool-to-seat ring in the groove.
  10. Inspect the retaining rings for proper assembly.
    11. • Visually inspect the retaining ring in order to ensure that it is seated in the ring groove.
    • The opening in an installed retaining ring should face downward, toward the crankshaft.

    Object Number: 4968 Size: SH
  11. Measure the piston ring end gap.
  12. Measure all rings in their respective cylinders.

    13. Object Number: 4969 Size: SH
  13. Measure for ring clearance, using a feeler gage.
  14. Inspect the ring fit using the following procedure:
    15. 14.1. Fit each second compression ring to the piston on which it is going to be used.
    14.2. Slip the outer surface of the second compression ring into the respective piston ring groove in order to make sure the ring does not bind. If the ring groove causes binding, dress the groove with a fine cut file. Replace distorted rings.
  15. The oil ring is a two-piece ring, consisting of an expander and a scraper ring.
    16. 15.1. Install the oil expansion ring in the oil ring groove.
    15.2. Install the oil ring over the oil expansion ring.

    Important: 

       • When installing the compression rings, ensure that the marked side is facing the top of the piston.
       • The top compression ring is a keystone style ring.
       • While assembling the rings onto the piston, rotate the rings to check for binding.
       • If binding occurs, inspect the ring grooves for dirt or damage, such as nicks caused by improper installation.

  16. Install the second compression ring.
  17. Install the top compression ring.