For many decades, the Swiss Saurer Company was leading in the development of truck Diesel engines. They furthermore had branches in Austria and France. By the time the Second World War broke out, the Swiss and Austrian branches equipped their trucks exclusively with Diesel engines, while the French branch phased out the last gasoline-engine trucks in 1941.
In 1942, the transportation department of the Reich Security Main Office ordered 30 Saurer truck chassis with the aim of having the Berlin Gaubschat Company equip them with cargo boxes for an unspecified purpose. The Holocaust orthodoxy claims that these cargo boxes were designed or retrofitted to serve as mobile homicidal gas chambers, the so-called gas vans. It is safe to say, however, that these Saurer vehicles had Diesel engines, because had the goal been to deploy gasoline engines, other makes and models would have been much easier to purchase than Saurer gasoline trucks, who at that point in time might have been available only here and there as second-hand vehicles or in overstocked inventories (of which there were few during the war, if any). Diesel exhaust gas, however, is unsuitable for mass murder due to its low carbon-monoxide content.
(For more details, see Alvarez 2023, p. 28.)