The rear side doors--especially the driver side--in our 2001 Chevy Tahoe had gotten rather stiff, to the point where our 5-year-old son had trouble opening his car door. It turned out that there's a spring-loaded arm called the "door check link" that rides on two bars to provide the half- and full-open detents. That bar was scraping against its two mating bars rather than riding smoothly, and that resistance made the door hard to open and close. Fixing it was as simple as greasing the edges of that bar.
This process should be similar for all GM, Chevrolet, and Cadillac trucks, including the Suburban, Yukon, Escalade, Trailblazer and maybe even 4-door Sierra pickups. First, I'll show you the more thorough (yet difficult) way to grease the check link, then an easier way. Neither method takes more than 20 minutes.
|Pry the front & rear edges of the window switch|
Next, use that same screwdriver to dislodge the trim panel surrounding the inside door latch handle. Set the trim panel aside.
There are two 9/32" hex head screws holding the main interior door panel in place. One is at the lower hinge-side corner. The other is tucked under the grab handle. Remove those screws.
|Inside the door trim panel|
The door panel is now held in place only by a half dozen plastic L hooks (encircled in green in the above photo). Lift the door panel straight upward about one inch, then pull it away from the door a few inches. The courtesy light (encircled in orange in the above photo) is still plugged into the panel, so slide the light out of its fixture and leave it hanging by its wire from the main door.
|Peel back the water deflector|
to expose the check link
You can now see the inner half of the check link, and its shape will make its function more obvious. As you can see from the missing paint, both edges of this bar rub when the door is opening and closing. The factory service manual says that door mechanisms should be lubed with "multi-purpose lubricant GM P/N 12346241." This is reportedly similar to white lithium grease, which I had on hand. I wiped some that all over both edges of that bar, closing the door repeatedly to work the grease around the other mating surfaces. You'll immediately be able to see how much easier the door moves.
|The check link mechanism|
Once the door moves smoothly enough for your liking, reverse the process to reassemble the door. During reassembly, make sure that the door lock lever (encircled in blue in the above photo) connects to the lock switch properly.
The above process isn't terribly difficult, but if it's still too much for you, you can access part of the check link without disassembling the door.
|Outer end of the check link|
and its protective grommet
Curiously, while I've had to grease the driver side door twice in 15 months, I've never had to grease the passenger side door. Google tells me that this is a common problem, though, so I suppose I'm just lucky with the passenger side rather than unlucky with the driver side.
Any comments or questions? Speak up in the comments below!