Mine have never been adjusted. I was taking off my side steps for this coming weekend and happened to notice the bolt. Some of the top threads on the bolt seem to be "cleaner" than the bottom ones so it would seem the bolt backed out, BUT those bolts are under some big pressure created by the torsion bars, so one would think backing out would be difficult.
I called and spoke to the local dealer's Hummer service guy and he wants me to bring it in since both bolts are adjusted so far apart. By the way, I put a quick measuring tape to the front end and there does not seem to be much difference in height from side to side.
My luck they will have to order a new torsion bar and I won't get to go to the Happening this weekend.