Self - Changing Gears made semi-automatic transmissions for British Rail .
Voith manufacture turbo - transmissions for railcars and diesel multiple units which contain various combinations of fluid couplings and torque converters .
Self - Changing Gears made semi-automatic transmissions for British Rail , and Voith manufacture turbo - transmissions for railcars and diesel multiple units which contain various combinations of fluid couplings and torque converters .