D237 was a class 40 diesel engine that was built in 1959 for British Rail by English Electric Vulcan Foundry. D237 was used on express trains but along with its siblings were slowly replaced by newer diesels. D237 appeared in "The Railwayman's Film" in 1960. D237 was renumbered to 40037 in 1974 and served as that indenity intill being withdrawn and scrapped in 1983.