Service Procedure

This Procedure involves modification of the tailgate key cylinder assembly located at the outside, center of the tailgate below the window.

For 1982 through 1988 model year vehicles, only the key cylinder base requires replacement -- reuse the original dust cover assembly unless it must be replaced due to weak/broken return spring or severe corrosion.

1981 and prior model year vehicles have a smaller diameter key cylinder hole in the cover assembly that may corrode and interfere with free rotation of the key cylinder. Therefore, both the base and cover assembly must be replaced on 1981 and prior models.

1. Remove the two 5 crews from the key cylinder dust cover using a hollow point Torx Driver Bit -- remove the cover.

Caution:
To avoid breaking the Torxdriver bit, be sure that the bit is full and squarely seated in screw head when applying turning torque. If need e , extra Torx bits can be obtained from your Parts Depot (P/N 80002368) or from a Snap-On tool source (P/N TTXR2SC2) -- bit size T2SH.

NOTE:
1975 and prior model year vehicles have one-way slotted type security screws to retain the dust cover. For those models, it will be necessary to drill and remove the screw heads for dust cover removal.

2. Remove the three Phillips head screws from the key cylinder base.

3. Remove the key cylinder base assembly from the tailgate.

NOTE:
This illustration shows the key cylinder-to-switch square shaft as a part of the assembly. If the square shaft is not present, it was likely removed per the December, 1987 interim notification letter (JE 8707). If so, the shaft should be retrieved from the vehicle glove box for installation later in this procedure.

4. Release the key cylinder from the base with a probe (such as a large paper clip) inserted through the access hole in the base.

^ Key must be in the key cylinder for cylinder removal.

^ Spring loaded retainer clip is in t e proper position for key cylinder removal when the smooth edge of key is toward the probe hole.

5. Remove the key cylinder and square shaft from the base and discard base. Retain the square shaft and key cylinder for later installation.

6. Thoroughly clean key cylinder tumblers with WD 40 or equivalent. Dry excess and then lubricate tumblers with supplied lubricant.

7. Insert the square shaft into the new supplied base.

8. Install the key cylinder In the base so that it engages with the square shaft. With the key in the key cylinder, fully seat the cylinder in the base (with notched edge of key up) until retaining spring engages.

9. Install the base assembly to the tailgate.

^ Key removal warning decal on the base must be up.

^ Notched edge of key must be "up" when inserting the square shaft into the switch hole.

10. Secure the new base to the tailgate using the new, supplied Phillips head screws.

11. If key cylinder cover is to be reused, clean cover pivot area with WD 40 or equivalent. For both new and reused covers, lubricate the dust cover pivot pin and spring with the supplied lubricant P/N 83000040.

^ Reuse the original cover for 1982 through 1988 models unless the cover return spring is weak or broken or if the pivot is severely corroded.

^ A new cover should be installed on all 1981 and prior models, and on 1982 and later models that are found to have spring or corrosion damage.

^ If replacement is required, use cover assembly P/N 83000039, and lubricate as shown prior to installation.

12. Secure the dust cover assembly to the base with the new, supplied Torx screws.

13. Test system for proper operation -- The glass should stop moving each time the key is released.

(A) Fully lower the tailgate window.

(B) With window open, allow the dust cover to rest against the key.

(C) With the dust cover resting against the key, turn the key so that the window begins to close (see below).

Note that with the new base, the key cylinder cover pivot is now at the "4 o'clock" position instead of the original "12 o'clock" position. This allows the spring loaded cover to push the key toward the "off" position.

(D) After the window closes about two inches, release the key. When you release the key, the window should stop moving.

(E) Repeat steps (C) and (D), raising the glass about two inches at a time and releasing the key, until the window is closed.

(F) After lowering the window again, repeat the above steps (B) through (E) a total of three times.

Important:
If the glass does not stop each time the key is released, proceed to replace the power tailgate window switch with P/N 56003167 following Service Manual procedures.

Contact your Zone Service Office or District Manager for prior work approval1 service codes (SRT, TIC, Supplier Code) and Time Allowance for switch replacement. Submit a separate claim for switch replacement reimbursement.

When replacing a switch, be sure to adjust and tighten so that the square hole in the switch is centered with the key cylinder hole in the tailgate. This will ensure that the square shaft from the key cylinder will mate properly (with minimum angle) with the switch hole when the cylinder base is installed.

After switch replacement is completed, repeat step 13 (Test) of the Service Procedure to ensure proper operation.