1966 for the Western Star. After the startup of Amtrak in 1971, Great Northern Railway successor Burlington Northern Railroad converted all fourteen SDP locomotives to freight service. The Erie Lackawanna Railroad ordered 14 SDP45s in 1969 and 1970. Intended only for freight service, these units had standard (angled) long hood ends, and the extra space aft of the radiators had concrete ballast where a passenger unit would have a steam generator and venting. Their longer frames permitted a larger fuel tank which gave the locomotives a greater range between fuel stops. EMD later redesignated these as SD45Ms. Roster Rebuilds One Burlington Northern Railroad SDP45 6599 was retrofitted with an articulated four-axle truck by EMD in 1983-84, converting it to an A1A-B+B wheel arrangement. The middle traction motor in the lead truck was removed and placed in the rear truck. The rear truck, called the HT-BB, for High Traction B+B arrangement, was tested successfully but advances in traction motors obviated the need for four-axle trucks. This testing was not related to the development of the HTCR three-axle radial truck first seen under EMD SD60s and SD60MACs and made standard on the early SD70 series. Southern Pacific Railroad 8691-8696 were SD40M-3 rebuilds done by Morrison-Knudsen. They were ex-EL 3654, 3668, 3666, 3665, 3662, and 3659. It is this group that most surviving SDP45s belong to. Preservation Erie Lackawanna Railroad 3639, later Conrail 6670, was listed as being preserved at the Virginia Museum of Transportation, although the museum's collection list does not show it. In August 2018, Youngstown Steel Heritage announced their intention to purchase 3639 and move it to their museum, with the goal of restoring it to operating condition, and eventually back to its original number and paint scheme. In September 2018, the group announced that they had successfully purchased the locomotive; however, the current status of the project is unknown as the related pages have since been taken down. References Shine, Joseph W. (1992). Great Northern Color Pictorial - Volume 2: Division Assignment, Second Generation Diesels, The Big Sky Blue Era. La Mirada, CA: Four Ways West Publications. Strauss, John F. Jr. (1998). Great Northern Color Pictorial - Volume 5: Rocky's Robe of Many Colors. La Mirada, CA: Four Ways West Publications. Sarberenyi, Robert. EMD SD45 and SDP45 Original Owners. Retrieved on August 27, 2006 EMD's SD45 and SDP45 - Original Owners. Retrieved on May 27, 2009 Preserved EMD Locomotives