The VW Type 166 Schwimmwagen, literally Swimming Car was amphibious four-wheel drive off-roaders, used extensively by German ground forces during the Second World War. The Type 166 is the most numerous mass-produced amphibious car in history. The light weight of this vehicle of just about half ton, permitted crossing of muddy areas, since only two men were sufficient to keep this vehicle moving. For reconnaissance and liaison missions, water had to be crossed frequently, which was impossible with other vehicles.
All Schwimmwagen were four wheel drive only on first gear and had ZF self-locking differentials on the front and rear axles. Just like the Kubelwagen, the Schwimmwagen had portal gear rear hubs that gave better ground clearance, while at the same time reducing drive-line torque stresses with their gear reduction at the wheels. The Schwimmwagen could go up to 50 miles per hour on land.
When crossing a body of water a screw propeller could be lowered down from the rear deck/engine cover. When in place a simple coupling provided drive straight from an extension of the engine's crankshaft. This meant that screw propulsion always drove forward. The Schwimmwagen could go up to 6 mph in the water. For reversing in the water there was the choice of using the standard equipment paddle or running the land drive in reverse, allowing the wheel-rotation to slowly take the vehicle back. The front wheels doubled up as rudders, so steering was done with the steering wheel both on land and on water. For steering the Schwimmwagen the personnel inside the schwimmwagen could also use the aforementioned paddles.