75 2000 Clutch

Worked the 2000 very hard the other day pulling a chisel plow through a weeded field. As I worked harder and harder, it got harder and harder to shift gears. (When i started it, clutch operated easy). Had to bring the rpms down sometimes to go from 4th to reverse. Is this an indication I need a new clutch? (I did have a cinder block depressing the petal all last winter).

Don't think that is a 1975 2000.

Disregard that. I thought the tractor in the back was a 3000

Yes the front is a 4000 as witnessed by the chrome cap on the top front of the hood and the white and blue paint. 2000 has no chrome and paint is all the
same color cept the wheels.

On the clutch, if you were wearing the clutch out, springs getting weak or disc worn, you would be slipping under load....tractor would be slowing down in
ground speed and revving in rpms.

I'd take your tranny fluid is getting hot and thinning out reducing the drag on the non synchro gears forcing you to drop the rpms to get it to sync up and
shift. If you are running 134 in the tranny that can happen. I you backed the truck up to what you are using in your 4000, aka 85w-90 gear oil you probably
wouldn't be having that problem. Since the tranny is a separate sump and the hyd-diff share a sump it wouldn't hurt you to swap tranny fluid.

I currently have the '63 2000 and recently changed over from gear oil to trans hyd fluid. Did notice more noise and less synchronization when shifting. But
it's in and it's going to stay. Reason I changed is that for the last 25 years or so I've had it, its had pin holes in the hydraulic tubes running through the
tranny sump (identified by Soundguy) and the tranny takes about 3 months or so to accumulate enough fluid to drain it out the "full" port on the right side
of the tranny casting about half way up. So when I changed it, since it'd been running on it anyway I decided to filler up with 134.

I am running 134, not slipping under load.
Yes, picture t is 1962 4000 and 1975 2000.

Looks like you're good to go. Nice.