The fourth generation of Buick Roadmaster was introduced for the 1942 model year. This updated Roadmaster was larger on the outside and the inside, and was offered in coupe, sedan, convertible, and station wagon body styles. The fourth generation Roadmaster was fitted with a 320ci (5.2L) inline eight engine, and was produced until 1948, when it was replaced by the Fifth Generation Buick Roadmaster.