Cub Cadet hydrostatic drive problems

[njt268]

I own a 1987 model Cub Cadet Garden Tractor with an 18 horse Kohler engine, Hydrostatic Drive, and 340 hours of use. The Hydrostatic drive started to slip a little and the speed lever would drift back toward neutral. There was also some vibration. I tightened the lever which ended the drift problem but not the loss of speed or the vibration. Next I noticed hydraulic fluid bubbling up out of the filler tube. Took off some of the sheet metal and found that the area where the drive shaft connects to the front of the tranny was loose and wobbly and that the cross hole in the tranny input shaft had been wallowed out very large. Someone had replaced the pin with a small bolt! The bolt was almost totally worn through to nothing.
Could the vibration have ruined my make up pump on the front of the tranny? Or did I blow an internal seal?
Tractor hardly moves at all anymore. I don't think it's the check valves since the problem is the same in forward and reverse.
HELP!

 

[beenthere]

Which post should we respond to?

 

[njt268]

New to the site and didn't know where this belonged, repairs? or hydraulics? so I put it in both. Sorry for any confusion. Any help would be much appreciated.

 

[Rtwinger]

Is the hydrostatic transmission on my cub cadet model 2206 worth rebuilding. I have about 500 hrs on it.
Cub cadet installed a new trans. at less than 50 hrs. I Do admit that I do perform other tasks besides mowing with my model 2206, like pull a 42" yard aerator of substantial weight and a small 42" disc harrow.
My brother also has a cub cadet but his has a cast steel diff. mine has a aluminium one. Was there a problem with the aluminium ones.
I do have extensive mechanical abilities and varrious tools in my lair.