1998 model, worked one day and not the next. No noise, no grinding. Shuttle shift causes reverse horn but no movement in forward or reverse.
There's a by-pass button (or disconnect switch) on the loader lever that may be stuck in. There is also one on the shift lever, but the loader handle is the one that sticks sometimes
I tapped on those buttons a little too hard already, but next try is to take the handle apart to look for bare wire or whatever. There's a good bit of rodent damage on the wiring so maybe that.
The Power Shuttle transmission electrical description begins on page 4-48 in the manual with the circuit diagram on 4-49. Both disconnect switches appear to be normally open in the circuit diagram.
Very well might not be in gear or in too high of a gear. Try making sure the shifter is in 1st gear. I tried moving mine once and didn’t realize I was in 4th gear and couldn’t understand why it wasn’t moving.
Bad wiring??