just wondering if any one can help! i lost 5th gear when i was towing my 5th wheel. someone told me that they had problems that year. the nut backs off.
1994 five speed 1 ton 4x4 dually.thanks, bob

 

Losing fifth gear is a common problem. The whole story?
The main shaft is not fully splined and the nut cannot hold the gear in place with high torque loads (towing).
The correct fix is a fully spline main shaft & new gear.
Many have gotten by with a new double lock nut and some even tack weld the nut.
Search is a problem because most people don't title the problem correctly.