Should have three drains, one just about directly under the seat, on on the lower units of each rear wheel. Filled thru a cap or plug on top of the transmission case in front of the seat
Not familiar with any of the Satohs, but every Mitsubishi I've ever seen were set up that way
No drain plug under the seat but there are two pipe plugs on the bottom of the rear case, one for each side. The refilling is done by removing a hard rubber plug near the transmission shifter. There is a tube filter on the lower right side held in by two small bolts. The case will hold about 3.5 gallons. There is a fill level plug on the left side near where your left heel would be, sitting on the tractor. The tube filter should be cleaned and inspected for holes. It is a fine steel mesh type filter. If there are holes get a new/used one.
