The Ford Super Duty engine is a range of V8 engines that were manufactured by Ford Motor Company. Introduced in 1958, the Super Duty engines replaced the Lincoln Y-block V8 (alongside the smaller Ford MEL V8 engines). By the end of the 1970s, the use of the Super Duty engine began to decline in heavy trucks in favor of diesel-fueled engines; in medium-duty trucks, variants of the similar-displacement (but higher-efficiency) 385-series V8s became more commonly used. In 1981, Ford withdrew the Super Duty engine line.