Amtrak SDP40F diesel locomotives

Amtrak SDP40F diesel locomotives were derived from the best-selling SD40-2 platform but were far from a success on their own. The SDP40F shared its 72-foot, 4-inch frame with the predecessor passenger unit FP45 from 1967. Internally, however, it was akin to a 3,000 hp SD40-2 with a steam boiler added. That should have been a recipe for success with 3,962 SD40-2s, and more derivative units, built from 1972 to 1988.

Amtrak’s initial order was for 40 units numbered 500-539, delivered in June 1973. A subsequent order for 110 additional units was delivered April-August 1974, Nos. 540-649. The first 40 SDP40F units had noses that came to a point; subsequent units did not. One major difference from the earlier F45 and FP45 cowl units is the absence of a front walkway and handrails on the SDP40Fs. Several units also had bars installed over the windshields to deter rock-throwing vandals.

The units, the first purchased new, were delivered in Amtrak’s then-standard “phase 1” paint scheme with a red nose and large “pointless arrow” on their flanks. They were subsequently repainted into the “phase 2” scheme of two equal red and blue stripes set off with thin white stripes. Some units even received the “phase 3” scheme of three equal red, white, and blue stripes in the early 1980s.

For almost a decade, the Amtrak SDP40F diesel locomotives were the standard power on long-distance trains. However, some (possibly track-caused) high-profile derailments in the 1970s led to the removal of Amtrak SDP40F diesel locomotives from several host railroads at the time. That, plus the gradual change to locomotive-generated head-end power led to the units’ early retirement in the mid-1980s.

A majority were returned to EMD where components from 132 units were recycled into Amtrak’s new HEP-equipped, four-axle F40PH locomotives. Those units are designated as F40PHR to indicate they include components originally installed on the SDP40F units, but they are externally identical in appearance to other F40PHs.

However, 18 SDP40Fs were traded to Santa Fe in 1984-1985 for 25 CF7 and 18 SSB1200 switchers. They were rebuilt and classified as SDF40-2 units, serving for successor Burlington Northern Santa Fe into the early 2000s. One notable change in the rebuild is the notching of the front nose corners to accommodate a front walkway and handrails, a feature noticeably absent from the original SDP40F design.

One of these rebuilt freight units, No. 6976, gained fame in July 2002 when contractor National Railway Equipment released it in a blue-and-silver Warbonnet scheme honoring major intermodal shipper Maersk Sealand. It is preserved at the Nevada State Railroad Museum in Boulder City.