GM Service Manual Online
For 1990-2009 cars only
  1. Set the parking brake.
  2. Block the front wheels.
  3. Loosen the lower mounting of both shocks.
  4. Raise and lower the bottom of each shock, noting the rate of jounce and rebound of the shock absorber. Shock absorbers are non-adjustable and non-repairable. Replace both shocks if you detect a definite rate differential.