As the war broke out, Gräf & Stift started manufacturing trucks in order to meet wartime demand, which, together with buses and special vehicles, became the company's main business and enabled it to flourish in a rather difficult time. Manufacturing of passenger cars was resumed only in 1920, with a 2-litre intermediate-size model, " Typ VK". The "VK" remained in production until 1928 (since 1926 as the modernized "VK 2"), but already in 1921 Gräf & Stift returned to making luxury cars, with a range of large six-cylinder models available through the 1920s and early 1930s. In 1930, the company presented its first eight-cylinder car, the sumptuous "Typ Sp 8", in 1937 superseded by the "Sp 9".