[mrjeep81]

I am currently working on a 2084. It acted as you describe. The plates on the transmission wear excessively. Too much play causes weak inconsistent reverse. Numbers 16 and 22 in this diagram is what I replaced. I sourced them from CC Specialties. They are fantastic to do business with. I also shimmed #25 to reduce slop. If you a currently drive the tractor, with the tunnel cover off, move in reverse while watching your current linkage. CAREFULLY push the plates with your thumb, in the needed direction and see if the tractor responds favorably.
There is also a good video someone on utube has showing the excessive wear.
Look for “sloppy cub cadet linkage”.