How to replace ignition lock tumbler?

Here is how you replace the ignition tumbler

Disable the SIR system. Refer to ZONE 3.
Remove the upper and lower trim covers. Refer to Steering Column Trim Covers Replacement.
IMPORTANT: The abrasion sleeve located on the steering column wire harness assembly must be reinstalled. Make note of what connector is coming out of the abrasion sleeve for installation purposes.

Remove the wire harness strap (2) from the steering column and the wire harness assembly (1).
Fig. 36: Remove Wire Harness Strap & Wire Harness Assembly
Courtesy of GENERAL MOTORS CORP.
Slide the 2 connectors (2) of the turn signal and multifunction switch assembly out of the bulkhead connector (1).
Fig. 37: Slide 2 Connectors Out Of Bulkhead Connector
Courtesy of GENERAL MOTORS CORP.
Rotate the key alarm connector (1) 90 degrees.
Pull the key alarm connector (1) out of the ignition lock cylinder case (2).
Remove the passkey connector from the ignition lock cylinder case (2).
Fig. 38: Key Alarm Connector & Ignition Lock Cylinder Case
Courtesy of GENERAL MOTORS CORP.
Insert J 42759 into the ignition lock cylinder case (1) and slide the ignition switch (2) out

Check out the diagrams (Below). Please let us know if you need anything else to get the problem fixed.

I would start by trying to adjust the linkage. It sounds like it isn't allowing the shifter to return to the park position. If not you need to replace the tumbler here is how. Check out the diagrams (Below). Please let us know if you need anything else to get the problem fixed.

Check out our tips on this common problem to see if you can fix it without replacing lock cylinder.

https://www.2carpros.com/first_things/why_wont_my_ignition_switch_turn.htm

Here is how to change the ignition lock out. Check out the diagrams (Below). Please let us know what happens.

I am attaching the processes for each one of these components however, you should be able to just replace the damaged parts and then do the key programming feature that is included as well and the vehicle will be fine. The cylinder/housing just contain the ring to pick up the key.

Review the material and let us know if you have other questions.

Do you have a scan tool that can reset the security system to the new ignition cylinder? If not you can change it out, but the truck will not start until it is coded correctly.
Also if the current cylinder does not operate it gets much more difficult.

Removal is simple.
Disconnect the battery negative cable.
Remove the lower trim panel below the dash.
Remove the top and bottom covers from the steering column.
You must check for two pan head tapping screws in the lower trim before removal.
You must check for one TORX (R) head screw in the upper trim cover before removal.
(These may or may not be there, it depends on build date and if someone else worked on the truck and broke the tabs that normally lock the covers in place

Remove the steering wheel
If you have tilt wheel you may be able to skip removing the lower trim panel or the wheel, I have had a 50/50 mix on that, you can move the wheel up/down to get room to remove the covers.

Now insert a small allen wrench into the hole above the cylinder.
Insert the key and turn the cylinder to the "run" position.
Push down on the release pin and pull the cylinder straight out.

Reverse the process to install the new one.
If anything moved the ignition switch in between replacement, use a screwdriver to reach into the switch, turn it to start and let it return to the run position.

Then program the security system so it recognizes the new cylinder and key.

What is the issue with the current cylinder? Lost key? Key does not work?

If the key does not turn then unfortunately you will not be able to remove it without drilling it out. So you are going to have to run a drill into it so that you hollow out the tumblers and then the key will turn. Clearly it will not start the vehicle this way but you will be able to remove it and replace it at that point.

Here is a guide that talks about this:

https://www.2carpros.com/articles/ignition-switch-wont-turn-stuck

I attached the instructions below on how to change it out.

Let us know if you have questions. Thanks

Hello,

I have included the information that you requested in the diagrams down below. Please go through it and get back to us and let us know how it turns out. If you have any other vehicle related questions, please, don't hesitate to ask. That is what we are here for.

Thanks,
Alex
2CarPros

Hello,

This sounds like you might need to do a relearn procedure. I have included a description of the anti theft system, how it works, and the factory relearn procedure in the diagrams down below. Please go through the information and the guide and get back to us with what you able to find out, please.

Thanks,
Alex
2CarPros

Hi and thanks for using 2CarPros. Com. I have attached the procedure for replacing the ignition switch. Check to make sure you did not miss anything. Additionally, there are several pictures which related to these directions.

SERVICE AND REPAIR
IGNITION SWITCH REPLACEMENT-ON VEHICLE

Removal Procedure

Disable SIR system, refer to See: Body and FrameAir Bag(s) Arming and Disarming
Remove the trim covers from the column, refer to Steering Column Trim Covers-Replacement. See: Steering and SuspensionSteeringSteering ColumnService and Repair- With Tilt Column
Disconnect the steering column electrical connectors.
Remove the wire harness assembly (1) from the wire harness strap (2).
Remove and dispose of the small wire harness straps from the wire harness assembly (1).
Slide the two connectors (2) of the turn signal and multi-function switch assembly out of the bulkhead connector (1).
Remove the key alarm connector (1) from the lock module assembly (2).
7.1. Rotate the key alarm connector (1) 90 degrees.
7.2 Pull the key alarm connector (1) out of the lock module assembly (2).
Remove the two tapping screws (2) from the ignition and key alarm switch assembly (1).
Installation Procedure
Install the ignition and key alarm switch assembly (1) onto the lock module assembly.
Notice : Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Screw the two tapping screws (2) into the ignition and key alarm switch assembly (1).
Tighten the two tapping screws to 1.5 Nm (13 lb. In).
Install the key alarm connector (1) into the lock module assembly (2).
4.1. Push the key alarm connector (1) into the lock module assembly (2).
4.2. Rotate the key alarm connector (1) 90 degrees so that the key alarm connector (1) locks into place.
Slide the two connectors (2) of the turn signal and multi-function switch assembly into the bulkhead connector (1).
Connect the steering column electrical connectors.
Attach new wire harness straps to the wire harness assembly (1).
Install the wire harness assembly (1) to the wire harness strap (2).
Install the trim covers to the column, refer to Steering Column Trim Covers-Replacement. See: Steering and SuspensionSteeringSteering ColumnService and Repair- With Tilt Column
Enable the SIR system, refer to See: Body and FrameAir Bag(s) Arming and Disarming

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Review the directions and pictures and let me know if you do not find what you need or have other questions.

Take care,
Joe

Hello,

Yep it sounds like the key tumbler had fallen apart and needs replacement. Here is some guides (below) that will show you how to get the job done.

Please let us know what happens.

Cheers, Ken