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Front Side Door Lock Cylinder

WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.

The front side door lock cylinder uses 7 of the 10 key cut positions, 4-10 when counting from the key head. The tumbler orientations alternate in adjacent locations from side to side with 4 on each side.

    Fig 1: View Of Front Side Door Lock Cylinder Components
    GM1987986Courtesy of GENERAL MOTORS CORP.
    IMPORTANT: The front side door lock cylinder tumblers (3) are not self-retaining and must be held in place if the key is not fully inserted into the lock cylinder or until the cylinder (1) is assembled into the case assembly (4).
  1. Hold the uncoded cylinder (1) positioned so the side with 4 tumbler spring holes is facing upward, as shown.
  2. Insert one tumbler spring (2) each into the 4 tumbler spring holes.
  3. The first tumbler to be loaded will be key cut position 4, the fourth number in the key code. Determine the cut depth at this position and install the corresponding tumbler (3) into the tumbler slot nearest the front of the lock cylinder assembly, the end where the key is inserted.
  4. In the same manner, determine the cut depth and corresponding tumbler and install the 3 remaining tumblers (3) into the tumbler slots located at key cut positions 6, 8, and 10.
  5. Check for correct loading by holding the tumblers (3) in position and fully inserting the matching key into the cylinder (1). All tumblers should be flush with the outside diameter of the cylinder.
  6. Rotate the cylinder (1) so that the side with 3 tumbler spring holes is facing downward and then remove the matching key. Remember the tumblers (3) are not self-retaining and must be held in place.
  7. Insert one tumbler spring (2) each into the 3 tumbler spring holes.
  8. The first tumbler to be loaded will be key cut position 5. Determine the cut depth at this position and install the corresponding tumbler (3) into the tumbler slot nearest the front of the cylinder.
  9. In the same manner, determine the cut depth and corresponding tumbler and install the 3 remaining tumblers (3) into the tumbler slots located at key cut positions 7 and 9.
  10. Check for correct loading by holding the tumblers (3) in position and fully inserting the matching key into the cylinder (1). All tumblers should be flush with the outside diameter of the cylinder.
  11. Lightly lubricate tumbler (3) surfaces using the lubrication provided.
  12. Hold the case assembly (4) with the pre-staked detent spring retainer facing downward.
  13. First insert one detent spring (5) and then one detent ball (6) into the detent spring hole located to the rear and inside of the cylinder case assembly (4). The detent spring and detent ball are not self-retaining and must be held in place until the coded cylinder is installed into the case assembly.
  14. CAUTION: Wear safety glasses in order to avoid eye damage.
  15. With the matching key fully inserted into the coded cylinder, install the coded cylinder into the case assembly (4). Make sure the detent spring (5) and detent ball (6) are held in place until the coded cylinder is fully installed. The detent ball should line up with the V-shaped groove on the rear of the cylinder, which will prevent the detent spring and detent ball from falling out of the case assembly.
  16. Remove the matching key being careful to keep the coded cylinder (1) fully inserted into the case assembly (4).
  17. Insert one shutter spring (7) each into the 2 shutter spring holes located on the front face of the cylinder (1).
  18. Install the shutter assembly (8) into the recessed area on the front face of the cylinder (1). Be sure that the ends of the pin on the shutter assembly are positioned in the pin cavities located in the front face of the cylinder.
  19. Install the lock cylinder cap (9) by aligning the drain hole in the cap with the bottom of the case assembly (4). Snap the cap into place with light hand pressure. Be sure the cap is securely retained on the case assembly. Also, be sure that the shutter springs (7) push the shutter assembly (8) up against the inside surface of the cap.
  20. Install the lever (10) onto the end of the cylinder (1).
  21. Install the retaining ring (11) in the groove at the end of the cylinder (1) to secure the lever (10) to the cylinder.
  22. Snap the rod retainer (12) into the hole in the lever (10).