The earlier cars used a Rover engine from the 1948 Rover 75. A four-speed manual transmission was used with a column-mounted gear change at first and floor-mounted unit from September 1953. At first the gearbox only had synchromesh on third and top but it was added to second gear as well in 1953. A freewheel clutch, a traditional Rover feature, was fitted to cars without overdrive until mid-1959, when it was removed from the specifications, shortly before the London Motor Show in October that year.