Although Fred Duesenberg was a self-made man who lacked formal technical training, his engineering expertise influenced the development of the automobile. He is credited with introducing the eight-cylinder car in the United States and four-wheel brakes, in addition to other mechanical innovations that included overhead camshafts and four valves per cylinder. He was also patentholder of his designs for a four-wheel hydraulic brake, an early automatic transmission, and a cooling system, among others. The Auburn Cord Duesenberg Automobile Museum, which opened in 1974 in former the headquarters building of the Auburn Automobile Company in Auburn, Indiana, includes examples of Duesenberg-designed cars.