Oh man, it sounds like the cable came out of the transfer case. It is usually held in there with a screw or bolt. If it came out you might have lost some fluid which is making it shift funny. But an auto tranny is separate of the t-case with its own fluid so maybe not. You better get under there and look, its the only thing I can think of... :unsure:
I think the 92-96 Broncos uses a VSS (vehicle speed sensor), which will affect tranny operation. The VSS is located inside the rear differential, so check the wiring . I had this item go out on my 98 Z-71 last month, and it also killed my ABS (no brakes!).
the speedo cable has a metal gear on the end of it that sticks into the transmission. pull the cable out and make sure the gear is still there. if not, it has probably been ground up by the trans and will be stuck to the end of your transmission sensors, which are magnetized. this could be why your transmission is shifting funny