GM Service Manual Online
For 1990-2009 cars only

1st/2nd, 3rd/4th, 5th/6th Synchronizers

Important: Synchronizer components are not interchangeable. Keep all the synchronizer components separate. The synchronizer hubs and the sliding sleeves are a selected assembly. Keep the hubs and the sliding sleeves together as originally assembled.


    Object Number: 4810  Size: SH
  1. Scribe a mark on the synchronizer hub and on the sleeve. This will help you to reinstall the parts in the same position.

  2. Object Number: 38443  Size: SH
  3. Remove the synchronizer springs. Use a small-blade screwdriver.

  4. Object Number: 38444  Size: SH
  5. Remove the synchronizer sleeve and the keys from the hub.

Reverse Synchronizer


    Object Number: 4810  Size: SH
  1. Scribe a mark on the synchronizer hub and on the sleeve. This will help you to reinstall the parts in the same position.

  2. Object Number: 38335  Size: SH
  3. Remove the synchronizer spring. Use a small-bladed screwdriver.

  4. Object Number: 38337  Size: SH
  5. Remove the synchronizer sleeve from the hub. Press against the inner hub.
  6. Turn the hub over. The keys will slide out from the hub.

  7. Object Number: 38343  Size: SH
  8. Remove the following parts using a small-blade screwdriver:
  9. 5.1. The synchronizer key retainer
    5.2. The synchronizer spring
  10. Discard the synchronizer key retainer.