The Centre Steer used a Rover 1.6 litre 4-cylinder petrol engine of 50 horsepower (37 kW). This was coupled to a 4-speed manual gearbox from the Rover P3 saloon. This unit was coupled to a Willys/Ford 2-speed transfer gearbox taken from a Jeep. This not only allowed the selection of a lower set of 'crawler' gears but controlled the selection of drive to the front axle as well. The production 1948 Land Rover used the P3 gearbox, but an entirely different transfer box, designed and built by Rover, was fitted. This incorporated a Rover 'freewheel' mechanism to provide a permanent 4-wheel-drive system. The freewheel could be locked out to ensure full traction at both axles when off-road.