Got hung up in the swamp the other day and noticed only 3 wheeles were turning.......of course this was after my winch took a dump.I changed the oil a month and a half ago. Any suggestions

 

It would look like the pole gap is out! or you have a wire off on the main connection panel. The pole gap is not something I would touch. but check the wire's first.each wheel is independent.And you should have felt the bike pull to one side BAD. good luck. ken