Although the Duesenberg team had mechanical and fuel issues in the Indianapolis 500-mile race in 1919 and its entries did not finish that year, the team continued to race with better success in the 1920s. Several Duesenberg-designed racers also set speed records before Fred officially retired from auto racing after the Indianapolis 500-mile race in 1931. In April 1920 a Duesenberg racecar driven by Tommy Milton set a land-speed record of for a measured mile on the sands at Daytona Beach, Florida. In August 1920 Fred and Augie Duesenberg formed Duesenberg Brothers, a separate company for their auto-racing business. In 1921, Jimmy Murphy drove a Duesenberg racecar to become the first American car to win the prestigious Grand Prix at Le Mans, France.