In 1923, the first 24 Hours of Le Mans race took place, from May 26 to 27. But another event is noteworthy for the history, with a capital "h", of the automobile: the first diesel vehicles saw the light of day. And this time, we can say thank you to the Germans.

Before merging in 1926, Benz & Cie and Daimler-Motoren-Gesellschaft (DMG), two German manufacturers, lined up to release a diesel truck in the same year. The two machines were not similar in all respects. For Benz & Cie, the vehicle was fitted with a "  four-cylinder OB 2 diesel engine with an output of 33 kW (45 hp),  " writes Daimler on this site . This is a prechamber engine. For its part, Daimler-Motoren-Gesellschaft had opted for a direct injection engine. The two trucks had about the same horsepower. But above all, compared to a gasoline engine, diesel allowed "to  achieve a fuel saving of 86%  ".

A revolution. Also in 1923, the two manufacturers carried out road tests. For Daimler-Motoren-Gesellschaft, the truck makes a round trip between two factories located in Berlin and Stuttgart in the space of 10 days, i.e. nearly 1,300 kilometers. A feat for the time. The tests are also conclusive at Benz & Cie and the two companies embark on the mass production of diesel engines. In 1926, the two manufacturers merged, becoming Daimler-Benz Aktiengesellschaft and choosing Benz & Cie's solution, that is to say the prechamber engine, to equip the brand's next five-ton trucks.

The transition takes time, especially in the face of driver skepticism about diesel engines. With the help of marketing and support from the trade press, the five-ton diesel truck finally won over businesses and drivers. At the same time, Ferdinand Porsche, one of the three chief engineers, left the company to start his own business.

The end of an era ?  Almost a century later, diesel and gasoline vehicles are in the sights, and several manufacturers have announced that they will switch to production of 100% electric (or hydrogen) models. Several cities also intend to ban these machines from circulating, because they pollute too much. In France, Lyon , Strasbourg and even Paris have already announced the driving ban dates for these cars. And several states or countries ( Spain , England , etc.) will also ban the sale of diesel and gasoline within a few years. We can say that it is really the end of an era.

Photo credits: @Daimler