[nm156]

Hello, I also have a '99 burb and just went through the same problem. Gregory is right about the lube. What I did was take some brake cleaner and spray out the locking mechanism real good. Cleaning out all the old lube. Then I used the lube and it's been fine for about a year now. Now as far as opening the door, I don't know if you meant from the inside or out. I had a problem a couple of months ago where my driver door handle on the inside slowly broke off. It was a problem for a few weeks until finally it broke off in my hand. I replaced it myself, the trickiest part is getting the door panel off. It only cost me 35 bucks at the dealer and about an hour labor. Good luck. I almost forgot if you do it yourself you will have to drill out a 3/16 pop rivet that is on the handle assembly and replace it.