JD 855 Slow Transmission

[jimsing]

I have a 1997 855 with about 1200 hours. Over the last couple of years, on occasion the pedals would stick, not allowing you to travel at a normal speed. You can go slow though. I talked to a tech who said it was just sticking and to kick the pedals real hard. When I did that, I would end up breaking the bolt in the linkage but when I put it back together, it would work fine. I finally discovered that I could also just turn it off and wait maybe 5 minutes and it would work fine. Finally, it won't correct itself again. I could feel tension building up in the pedals when it was getting ready to stick.
I'm thinking that's there's pressure building up somewhere causing it.

If anyone has any ideas, please chime in. I'm hoping on some kind of an easy fix but not holding my breath. Any help/suggestions would be appreciated.

 

[Mechanos]

There really isn't much of anything inside the trans to wear out. There is a total of 5 check, relief and bypass valves (piston, spring, plug, etc.) in the case, though, that could be removed cleaned and/or rebuilt.

 

[Unclejoeussr]

I had the same issue, for months, finally figured out it was the seat safety pressure switch, it was not being depressed far enough to unlock the drive, likely due to a worn out spring. I was able to fix it immediately by removing one small spring connecting the pressure switch to the drive mechanism, disabling the safety.

It was easy to figure out once I knew where to look, to check if your problem is caused by the safety switch just pull up the seat, and press down on the switch (long metal thing sticking out can't miss it). While pressing that now also press the forward or reverse at the same time. *MAKE SURE TRACTOR IS IN NEUTRAL* if that fixes it then all you gotta do is disable the mechanism by removing the spring.

Hope that helps!