Self-Changing Gear Co
of Lythalls Lane, Coventry.
1928 Self-Changing Gears company founded by Major Walter Gordon Wilson and John Davenport Siddeley
1951 Private company: Self-Changing Gear Co. Maker of Wilson Gearboxes (see advert)
1952 Leyland Motors acquired (an interest) in the company, which owned the patents for the pre-selective type of epicyclic gearbox which Leyland had fitted to the RTL & RTW Titans it sold to London Transport. The company was working on a new type of direct-acting epicyclic gearbox at the time of the Leyland takeover.
1953 The new gearbox was announced as the Pneumocyclic.
1959 Leyland Motors increased its investment in the company
1961 Gear box and transmission equipment manufacturers. 570 employees.
1978 Maker of heavy duty transmissions; part of BL Commercial Vehicles
1982 Trackpower Transmissions, David Brown Gear Industries and Self-Changing Gears formed a major export sales alliance for Britain's two leading armoured fighting vehicle transmission manufacturers.[1]
1986 Leyland Vehicles sold the company to Cummins Engine Co[2] but the privatisation was not publicised for some months[3]
1989 Cummins sold the company to United Scientific Holdings which later became Alvis plc