Let's do some deductions real quick, your 84 is an early 84 build...... correct?
The early 84's still had the weak 5 speed 83 trans, and that is the problem it's just that simple. The first thing to go on those is 5th gear, sounds like it may be time to upgrade to one of the stronger trans. that came out mid 84 or above. Now I'm not a trans guru but some around here would know the best one to get, though I do know that a turbo trans has a lower 1st gear and is very desirable in the offroad community.
