speed truck, although they originally had GSC Commonwealth, but were re-trucked in early 1948. Seaboard chose less stable Commonwealth trucks which took up less room under the frame. None survive. References Diesel locomotives of the United States A1A-A1A locomotives A1A-3 locomotives DR-6 Passenger locomotives Locomotives with cabless variants Scrapped locomotives Standard gauge locomotives of the United States Standard gauge locomotives of Mexico Streamlined diesel locomotives