The process for overhauling the transmission is largely generic. Once you are sure there has not been an error (such as pushing the transit lever for that transmission, or the parking brake engaged, or a low fluid level) you have two basic possibilities: a broken gear in the transmission's drive train after the hydraulic motor, or gross leakage past the pistons of the hydraulic pump, hydraulic motor, or both. A leakage problem is either caused by sustained overheating or fluid contamination, but does not develop suddenly: drive is lost progressively. A broken gear is an all-or-nothing situation: one moment you have normal performance, the next moment you have nothing. Often the transition from all to nothing has coincided with some genius trying to do wheel-stands, or use the machine as a bulldozer.
