UP Introduces Centennial Locomotives
Named for the centennial of the Golden Spike Ceremony, the newest locomotives were put into high-speed freight service. The Centennial, which weighed in at 270 tons and measured 98 feet long, achieved 6,600 horsepower provided by two diesel engines mounted on one frame. UP purchased 47 units in all, called the 6900 series, between 1969 and 1971. Each ran more than two million miles before the locomotives were retired in 1986. UP 6936 was assigned to special service in 1985, and now travels on occasion as part of the UP Heritage Fleet.