An amphibious vehicle power train having an engine (2) with an output shaft (4), driving an input member (6) of a variable speed change transmission (11). The speed change transmission, which may be a continuously variable transmission is arranged to drive road wheels through an output member (8). The engine also drives a marine propulsion unit (24). The axis of the output member (8) is above the axis of the input member (6). Four wheel drive may be provided (FIG. 2).