Frozen door lock cylinder - suggestions?

[DeadheadNM]

Despite repeated use of penetrating oil the RH door lock cylinder in my 99 k2500 is still “frozen” such that twisting the key won’t rotate the cylinder. I can unlock it from the inside and the remote actuator works fine.

Unless anyone can give me some other suggestions I’m assuming I’ll have to disassemble the door to access the cylinder for (presumed) rust debridement.

Anything else to prep for if I disassemble the door? Clean, grease, and lube the moving parts? I’ve not yet dug inside the door of a GMT400.

[Just call me Sean]

Here's a picture of the back of the handle. They're kind of a pain to get out of the door. You press the tab on the bottom the screwdriver is pointing at and the lock pushes in (up in the picture) to remove it.

[sntrym95]

Pry up the power window/lock assembly and remove the connectors. Two screws in the arm rest, 4 tabs on the interior handle bezel, and a bunch of clips hold the door panel on. You have to pop off the little panel by the mirror first. Do it with the window up. Don't forget the courtesy light connector.

Once the panel is off, the exterior handle is held on by two 10mm bolts. A wobble adapter and a magnetic socket will be your friend for the one inside the door frame. Once the handle is loose, you can slide it out a little and release the rod from the pawl for the lock, then gently pull and twist it out. It takes some practice and is a tight fit. Tape the edges of the handle opening before you fully remove or install the handle if you're interested in keeping your paint job intact.

[DeadheadNM]

Thanks guys. I appreciate the advice.

[DeadheadNM]

Finally got around to tackling this. The cylinder is out. Odd, it rotates freely but over a very limited distance from say 12 to 12:30. Still fiddling with it.