Assembling and Coding Door Lock Cylinder

The front side door lock cylinder only uses seven of the ten cut positions, 4-10. The tumbler positions are staggered from side to side (4 on one side and 3 on the other). The left and right door lock cylinders are identical. The lock pawl determines which side of the vehicle the lock cylinder is on.

Fig 1: Exploded View Of Door Lock Cylinder & Components
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: The front side door lock cylinder tumblers (10) 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 (9) is assembled into the case assembly (11).
1. Hold the cylinder (9) so that the side with four tumbler spring wells faces up.
2. Insert tumbler springs (5) into the four spring wells.
3. Install the tumbler for key cut position 4 in the slot nearest to the front of the lock cylinder.
4. Install the three remaining tumblers, key cut positions 6, 8 and 10, on this side of the lock cylinder.
5. Inspect for correct loading of the tumblers (10) by inserting the key into cylinder (9). All of the tumblers should be flush with the outside diameter of the lock cylinder.
6. Turn the cylinder (9) so that the side with three tumbler spring wells faces up.
7. Insert the tumbler springs (5) into the three spring wells.
8. Install the tumbler for key cut position 5 into the slot nearest the front of the lock cylinder.
9. Install the two remaining tumblers for key cut positions 7 and 9 on this side of the lock cylinder.
10. Inspect for correct loading of the tumblers (10) by inserting the key into cylinder (9). All of the tumblers should be flush with the outside diameter of the lock cylinder.
11. Lightly lubricate the tumbler (10) surfaces using the provided lubrication.
12. Hold the case assembly (11) with the pre-staked detent spring retainer facing downward.
CAUTION: Wear safety glasses in order to avoid eye damage.
13. Insert one detent spring (3) and one detent ball (4) into the hole located to the rear and inside of the case assembly (11).
14. Insert the key into the lock cylinder.
15. Ensure the detent spring (3) and ball (4) are held in place until the cylinder is fully installed. Install the cylinder into the case assembly (11). The detent ball (4) will line up with the V-shaped groove on the rear of the cylinder.
16. Carefully remove the key, keeping the lock cylinder (9) inserted into the case assembly (11).
17. Insert one shutter spring (8) into each hole located on the front of the cylinder (9).
18. Install the shutter assembly (7) into the recessed area in the front of the cylinder (9). Ensure the ends of the pin on the shutter assembly (7) are positioned in the pin cavities located on the front face of the cylinder (9).
19. Install the lock cylinder cap (6) by aligning the two notches in the cap with the drain hole located on the bottom of the case assembly (11) and the corresponding feature on the top of the case assembly (11).

    Press the cap into place with light hand pressure.

20. Install the appropriate lever (2).
21. Install the retaining ring (12).
22. Snap the appropriate rod retainer (1) into the hole in the lever (2).