Nissan Repair: 94 Altima, manual. Stuck in revers gear, external linkage, plastic bushings

Question
Sometimes when I reverse up a steep incline my 94 manual Altima will get literally stuck in reverse gear, it won't shift out. The clutch works, and I can drive in reverse, it will kill if I let off the clutch because it's in gear. The way we have gotten un-stuck is by driving it backwards up hill and then let it roll forward (with the clutch in) and it will "un-lock."
From what I've read this could be a linkage or gear box problem??- what kind of repairs am I looking at? Expensive if done in shop, is it do-able at home?

Answer
Trisha,

I would think the shift linkage bushings are worn and that is causing the problem.  I would get the car up on jacks and find out what is loose in the shifter.  Have someone shift through the gears, with the car off and examine the linkage.  If the external linkage is tight and no bushings are gone then it would be internal to the transmission and that would mean that the shift forks or linkage are worn and will have to be rebushed.  The shift forks have plastic bushings and the shift rod has a bronze bushing.  But, if the bronze bushing was worn the transmission would probably be leaking so I would be looking at the external linkage first.  The nice part about the external linkage is you can replace it yourself.