GM Service Manual Online
For 1990-2009 cars only
  1. Run the engine at normal idle with the transmission in neutral and the clutch engaged.
  2. Disengage the clutch (clutch pedal depressed), wait approximately nine seconds and shift the transmission into reverse.
  3. If a grinding noise is heard, check the following for a dragging clutch.
  4. • Improper clutch pedal free travel
    • Weakened diaphragm spring
    • Rusted input shaft splines
    • Clutch facings broken or dirty with oil