ok have a 2001 3500 4X4 6 speed duely with 335,000 miles the problum is the transfer keeps jumping out of 2HI it dosent quite get to netural just kinda sits on the edge of the gears and grinds this truck is ran loaded most of the time but this happens weather loaded or not under power just had a shift fork and all new berings put in it to try to solv the issue and no luck all gears and shafts are in good order please help it is my dads truck my 01 just got out of the shop for the good old dana 70u rebuild lol we are not having a good time with them lately

 

there are also syncro's in the t-case that might be causing your problem. Are you running the right fluid, auto trans fluid. Check the Amsoil web sight.

 

corect fluid was just tor down and all parts looked fine