the tranny is going out, every rider made, over a period of time, they go, out.. inside the tranny are gears and nylon bushings, the gears are made of soft metal, they wear out, the bushings crumble an break, and they are forced up into the pump, causing it to become clogged.. then having to get a new tranny, or mower.. the maintence on the tranny is every 100 hours.. it uses hyrodlic fluid, when that oil gets hot.. it starts destorying internal parts.. so if its never been service. it will not move, or creep along.