Early 1940s Cadillacs –including the last of the V-16s- were some of the most beautiful models ever built, and they inspired “torpedo” styling throughout GM’s model lines. Headlights merged into fenders, and running boards and hinges disappeared. Improvements didn’t stop with looks, either. The 1940 Oldsmobile’s new Hydra-Matic was the first fully automatic transmission. Cadillacs had air conditioning and automatic heating, and all GM makes were getting the turn signals that Buick had introduced to car design in 1939. Convertibles were popular.

GM’s 25 millionth car –a silver Chevrolet- left the assembly line on January 11, 1940. But just as people were adjusting to prosperity after the Depression, auto production hit another roadblock. Early in 1942, a few weeks after the United States entered World War II, the U.S. government halted civilian car production. (The last cars produced before production stopped included chromeless “blackout” models). GM turned all its operations, from Canada or Australia, into a vast international network of military plants, suppliers and subcontractors. For a few years, GM was no longer the world’s largest maker of cars but the foremost producer of all kinds of Allied war supplies, from airplanes to tanks to ball bearings.

In 1948, GM rebuilt from rubble the German Opel operation it had been forced to abandon in 1940, and it finally caught up with a postwar surge in demand after 1945-46 strikes that blunted production.