A power train for an amphibious vehicle (34, 74) comprises an engine (18) and transaxle (22) arranged North-South, driving front (fig. 8), rear, or all four road wheels. A power take off (PTO) with optional decoupler (42) and constant velocity joint (56, figs. 4 and 9) drives marine drive means (40). The PTO may be taken from the input shaft of the transmission (44, fig. 4), and may use a synchroniser (65, figs. 5 and 6). The transaxle includes differential (24). The rear wheels may be set back from the differential outputs (fig. 7), with intermediate drives (47, 47') by chains or belts. A sandwich type (PTO) may also be used (53, fig. 9). In the four wheel drive embodiment, a PTO is required from the rear differential (33'). Decouplers (43, 45) may be provided in at least one wheel drive shaft on each driven axle. Numeral (31) denotes a centre differential.