On 5 February 1936, the first GM-Suisse car, a Buick eight-cylinder model, came off the conveyor belt.
During the war years, limousines were converted to army vehicles and railway trucks were repaired. As from 1946, production started again of Vauxhall and Chevrolet cars.

Opel models did not re-start until 1950. Over the years, the considerable variety of cars produced was gradually reduced to Opel Vauxhalls and from 1970 to 1975 to Rangers. The works was considerably expanded in 1949, 1957 and 1966. Five different GM’s with up to 3 different models came off the Biel conveyor belt ‘just in time’ and, depending on the order intake, in a motley order. This represented worldwide a unique logistical masterpiece.

It was originally planned to assemble 2000 vehicles annually, but in its heyday the works annually assembled up to 17,000 of them.