I just bought this truck and have been getting it running a bit at a time. Most recently, I replaced the red ***** on the hubs, reassembled them, and ran into a problem testing them. I locked the hubs, put the shifter in 4WD Low, and drove a few feet. When I try to unlock the hubs, they won't unlock, and the shifter won't move.

I don't know what to do and would appreciate any help.