On my way home from work I went to turn around in a snow filled parking lot and the truck wouldn't move in reverse. I circled the lot and contined home. Then I decided to test reverse in a plowed parking lot no problem. Then I turned on a unplowed road to talk to a freind. Once again no reverse foward fine. This time I took it out of 4 wheel drive and reverse was fine. The truck is a 91 with the 351w, 4EOD, and electric t-case. Dose anyone know what could cause this ploblem?

 

How odd. "won't move" as in rev as much as you like but no go? Or wants to move but can't seem to. Hopefully the former is true and you may be dealing with a MLPS adjustment issue. Otherwise I'd be worried about tranny or T-case.

 

Rev but no go