First model SD-45 freight locomotive built for the Southern Pacific Railroad in 1966. Originally numbered 8800, #7457 was the fIrst of 356 units delivered to SP, which had the largest fleet in the country. A V20 cylinder 645 diesel engine powered the SD-45 with 3600 horse power. It was used to pull freight from Ogden to the west coast over Donner Summit. It was acquired by the museum February 5, 2002.