from the early to late 1980's. Hydrostatic transmission. I think they came in the 3500 and 4500 series but cant swear to it. I am thinking it was a small 3 cylinder, you could mow forever on a tank of diesel. I can only remember ever having to work on one out of the bookoo's that the dudes I worked for sold. Same for the older Kubota series farm all type tractor that was pretty much a replica of the IH farmall. It took the Woods implements. that darn things just never broke down.

I had one up until a couple years ago when I traded it to my landscaping subcontractor for a Wheel Horse garden tractor.

Had a m4050 in mid 80s. It was somewhere near 50 hp only thing I can remember in that year series they changed parts so I had to take serial # in. Did my own repairs

Got one at home with a blown motor. Wife was cutting grass at property across the street and had a coolant leak. Got hot, started smoking so she freaked and drove it to the house instead of shutting it down. Has the Kubota D782 (I think) engine that's common to a lot of generators, etc. Rebuild kit is only around $500 but I can't find a machine shop local that can press sleeves in a bore that small. Bad thing is that those Kubota's have transaxles that don't unlock so it's tough to move.

Dad had a small L275 when i was growing up that got ran to death. Finish mowing with a woods. Had a small tiller for it also. It side raked a lot of hay. Theres an m4700 here grandad bought and i have a m9540. All good tractors for sure.

we had 4030su"s and m4700's in the mine. They were tough tractors for sure. We beat the guts out of them and they just kept going

I have a Kubota gas engine on my Snapper mower 24HP, 61 inch deck. Great engine, never any problems with it.

Had two - ZD1021 and Z222. Never had any issues :-)