My neighbour has a MTD Gold rider 25 hp Kohler and the hydro transmission has stopped driving completely. This guy takes meticulous care of all his toys. He mows ~ 1 1/2 acres of easy gentle slope lawn. .. no snow blowing or tilling. It's about 7 years old and looks like 1 or 2 light use years. We checked the belt ; the bypass rod ; no sign of leaks. It is presently at the local repair shop for diagnosis. I was wondering if anyone here has worked on or has experience with this sort of hydro transmission - any tips or advice are appreciated. ps : this hydro transmission has no drain plug, no dipstick, no fill cap .. ie: sealed unit ? John T.