The first generation of Oldsmobile Series 70 & 80 was introduced in 1939. The Series 70 and 80 were largely the same cars, with the 70 fitted with an inline six engine, and the 80 fitted with an inline eight. Production of the Series 80 lasted for one year (1939), before Oldsmobile renamed the model the Series 90, which was a precursor to the Oldsmobile 98. The Series 70 was also known as the Dynamic. Production of the first generation Series 70 was built until 1940, when it was replaced by the Second Generation Oldsmobile Series 70.