GM Service Manual Online
For 1990-2009 cars only

Important: The single-tube shock absorbers are highly gas pressurized and require a force of 445 N (100 lb) in order to initiate movement of the shock absorber rod. Do NOT dent or puncture the shock absorber assemblies.

  1. Examine all of the mountings for proper tightening. Loose mountings will cause a noise.
  2. If all of the mountings are intact, test each shock absorber by quickly pushing down, then lifting up, on the corner of the bumper nearest to the shock absorber which you are testing.
  3. 2.1. Use the same amount of effort on each test and notice the resistance on compression and rebound.
    2.2. Repeat this test on a similar vehicle having acceptable ride quality. The shock absorbers on both vehicles should provide the same feeling of resistance. If you notice much difference between the two vehicles, continue with the next step.
  4. Remove the suspected shock absorber.
  5. Shake the shock absorber and listen for loose metallic parts inside the shock absorber body. If you hear a suspicious noise, replace the shock absorber.
  6. Turn the shock absorber so that the lower mount is up and the upper mount and rod are down. Slowly compress the shock absorber. Do not allow the chromed portion of the shock absorber rod to pass below the black seal cover.
  7. Replace the shock absorber if you encounter a seize condition with more than 25 mm (1 in) of the chromed portion of the shock absorber rod exposed above the seal cover.