GM Service Manual Online
For 1990-2009 cars only

    Object Number: 177962  Size: SH
  1. Remove the six Hydraulic Valve Lash (HVL) Adjusters (1) from the cylinder head.
  2. Keep removed Hydraulic Valve Lash (HVL) Adjusters in order by their original position in the cylinder head.

  3. Object Number: 177950  Size: SH

    Important: Never disassemble the Hydraulic Valve Lash (HVL) adjusters.

  4. Do not apply force to the body of the adjusters or the oil in the high pressure chamber.
  5. Submerge the removed adjusters in clean engine oil until reinstallation. If the adjusters are left in the air, place with the adjuster bodies facing down. Do not place on the side or with the adjuster bodies facing up.