The Winton Motor Carriage Company was a real automobile manufacturer, but they never produced a "Winton Flyer" model. The vehicle in the film was created from scratch by Kenneth Howard, aka Von Dutch, especially for this movie. The car was designed to resemble a typical vehicle from 1904, but built to withstand the rigors of filming. Steve McQueen called the car "the real star of the picture", and took possession of it after filming ended. It remained in his automobile collection until his death in 1980. It can be seen in the Petersen Automotive Museum in Los Angeles, CA.
Charles Aidman was originally cast to play the role of Maury, but Lonny Chapman replaced him when Aidman was called in by "CBS" temporarily to replace Ross Martin on Martin's TV series "The Wild Wild West (1965)."
Will Geer and Juano Hernandez also co-starred in Intruder in the Dust (1949), which was also based on a novel by William Faulkner.