Saurer earned a major international reputation in automotive engineering. In 1908 – with the participation of Dr. Rudolf Diesel – the world's first automotive diesel engine was put on the test bench, in 1911 a Saurer truck crossed the North American continent for the first time, and in 1919 Saurer vehicles inaugurated postal bus services on Swiss Alpine roads. One of the most outstanding innovations in 1934 was the diesel engine with direct injection and the Saurer dual-swirl system. Passenger cars were manufactured by Saurer from 1898 to about the beginning of World War I, while the production of trucks and buses was a major manufacturing branch of Saurer starting in 1903. During the same period, Saurer achieved remarkable feats in the research and development of diesel engines. The enormous worldwide boom in automobile production led to large-scale series production abroad, a development that Saurer could not keep up with. Under the burden of the resulting structural problems, engine and commercial vehicle development and manufacturing were discontinued in 1982.