Oldsmobile
In the 1930s, Oldsmobile introduced the Series F and Series L on both Straight-Six and Straight-Eight engines while also introducing the Automatic Safety Transmission, which was originally built by Buick. In the 1940s, Oldsmobile introduces the "Hydramatic", which was the United States' first automatic transmission with four forward speeds. In the early 1940s, Oldsmobile body sizes ranged from 6 to 9 with Straight-Six and Straight-Eight engine, serving as the origin for Oldsmobile models such as the Oldsmobile 98 and Oldsmobile 88. Oldsmobile was a pioneer again in 1949 when the "Rocket" V8 engine was introduced. This engine proved to be popular for hot rodders and stock car racers. This engine would later be redesigned in the 1960s.