Sunbeam Commercial Vehicles was a commercial vehicle manufacturing offshoot of the Wolverhampton based Sunbeam Motor Car Company when it was a subsidiary of S T D Motors Limited. Sunbeam had always made ambulances on modified Sunbeam car chassis. S T D Motors chose to enter the large commercial vehicle market in the late 1920s, and once established they made petrol and diesel buses and electrically powered trolleybuses and milk floats. Commercial Vehicles became a separate department of Sunbeam in 1931.