GM Service Manual Online
For 1990-2009 cars only
  1. Clean the transmission housings in a suitable cleaning solvent. Air dry the housing.
  2. Inspect the countershaft bearing race bore for the following conditions:
  3. • Wear
    • Scratches
    • Grooves
  4. Replace the housing if the countershaft bearing race bore is worn or damaged.
  5. Inspect the housing for the following conditions:
  6. • Cracks
    • Damaged threads
    • Nicked mounting surfaces
    • Burrs
    • Scratches
  7. Replace a cracked housing.
  8. Clean up damaged threads with the correct size tap.
  9. Replace the housing if scratches, grooves or scoring cannot be removed with a soft stone or a crocus cloth.
  10. Inspect the machined mating surfaces for flatness. Check the mating surfaces with a straight edge.