Debuting for the 1934 model year, the Series 50 was the fifth evolution of the LaSalle. Initially introduced as the Series 350 before being renamed the Series 50, this new series of cars saw LaSalle shift from being based on Cadillacs, to being based on the Oldsmobile Series L. The Series 50 was originally powered by a 4.0L inline eight engine, but starting in 1937, a 5.3L Cadillac V8 engine was used. A wide range of open and closed body styles were offered, such as sedan, coupe, and convertible. Although previously, the coachbuilders Fisher and Fleetwood had built bodies for the LaSalle, the Series 50 was only bodied by Fleetwood. Production of the LaSalle Series 50 ended in 1940, when General Motors decided to discontinue the brand.