We had a late 70s Cub Cadet mower that was as tough as it came.
My dad bought another in the mid 80s that had hydrostatic drive. It wasn’t anywhere near as good the direct gear drive all-manual tank from a few years before.
Mine is very early 80’s. It was the same model as the late 70’s. It has hyrostatic drive but has a driveshaft from motor to rear end. Rear wheels have 5 bolts. The ones made now are very cheap. Also can’t get new replacement motors. I have a spare motor. Hopefully if outlasts me.