Ok, the day started well, but ended on a different note.
Started by checking all the linkage arms to make sure they were not spinning on the shafts, all was good.
Disconnected the hydraulic return line, ran a line to a clear tank to observe flow. In Neutral there was barley a trickle, in gear it was slightly better but not by much, this was at idle and while revving the motor.
Replaced the suction filter (yellow) and preformed the same test, flow was much better.
replaced the transmission filter (white) preformed the same test, another improvement in flow. Also put it into gear and I had wheel movement in both directions. Things were looking up. Maybe a clogged filter? Or so I thought.
Then I noticed the fluid that came out of the filters was yellow and cloudy, so a fluid change was next.
Drained the transmission and hydraulic tank. Fluid was dark coming from the transmission and yellow and cloudy from the hydraulic tank.
pulled the magnetic plug from the transmission. Plug was covered in metal shavings and had a ball bearing attached to it.
(see attached photos) the fluid also had a silvery streak of fine metal on the top of it in my catch pan.
I did not refill they hydraulic fluid and try to run, no sense wasting 3 gallons of UDT.
Having a Beer trying to think what to do next.