When used off-road or for towing, maintenance requirements are much greater than outlined here, so check the severe service maintenance schedule found in the owner's manual. Mitsubishi recommends using a flush machine to change transmission fluid, but if one isn't available, the fluid can be drained by disconnecting the hose to the cooler and, with the transmission in Neutral, running the engine for no more than one minute. This will get about two thirds of the fluid out, so refill and repeat to complete the change.