EMD SD45


The SD45 is a six-axle diesel-electric locomotive class built by General Motors Electro-Motive Division between 1965 and 1971. It has an EMD 645E3 twenty-cylinder engine generating on the same frame as the SD38, SD39, SD40, and SDP40. As of 2023, most SD45s have been retired, scrapped, or rebuilt to SD40-2 standards.

Design

A total of 1,260 were built for American railroads before the SD45-2 replaced it in 1972, along with the related SD45T-2 "Tunnel Motor."
SD45s had several teething problems. Reliability was not as high as anticipated; the twenty-cylinder prime mover was prone to crankshaft failure from engine block flex. Though it produced more than the 16-645E3 in the SD40, some railroads felt the extra horsepower was not worth it, even after EMD strengthened the block to eliminate crankshaft failures. At low speeds when tractive effort was adhesion-limited, the SD45 provided no advantage over the SD40.
Buyers included the Burlington Northern, Southern Pacific, Santa Fe, Pennsylvania Railroad, Norfolk and Western Railway, Great Northern Railway, Union Pacific, Denver and Rio Grande Western Railroad, Southern Railway, and Northern Pacific Railway. Many SD45s still exist, some rebuilt with sixteen-cylinder 645s for lease companies. SD45s and SD45-2s owned by Montana Rail Link retain their 20-cylinder prime movers. Wisconsin Central used to roster a large fleet of SD45s, but its sale to CN has resulted in the retirement of the entire fleet, with mass scrappings. Montana Rail Link is also starting to sell some for scrap.
EMD built seven examples of an experimental modification of the SD45, designated SD45X. The SD45X trialed several new features, including a more powerful EMD 645E3 engine producing up to 4,200 horsepower and a newly designed truck intended to have higher adhesion. Changes to the body included the use of different radiator fans and a flat rather than beveled end to the long hood. The SD45X was supposed to be a precursor to the proposed EMD 55 series of locomotives, however due to the failure of the 50 series locomotives, the cataloged SD55 was never put into production. Six of the SD45X locomotives were purchased by the Southern Pacific Railroad, with the seventh kept by EMD.

Accidents and incidents

SD45u

The Atchison, Topeka and Santa Fe Railway rebuilt 115 units into what had become the EMD SD45u. They were all renumbered as 5300-5483 between 1979 and 1989.

SD44R

In 1981, the Southern Pacific Transportation Company rebuilt a single SD45 into a single locomotive model designated the SD44R and numbered it #7399.

SD45R

The Southern Pacific Transportation Company rebuilt a total of 167 EMD SD45 units into EMD SD45R diesel locomotives at their own Sacramento Shops under the Southern Pacific's M-99 rebuild program and renumbered their units as 7400 through 7566. Most of them in their SD45 form were classified by the Southern Pacific as EF636-1, EF636-2, EF636-3, EF636-4, EF636-5 and EF636-6, but when they were all rebuilt under the Southern Pacific's M-99 rebuild program, they were classified as EF636LR-1, EF636R-2 and EF636LR-3.

SD40M-2

In 1993, the Southern Pacific Transportation Company had made a contract with Morrison–Knudsen to supply 133 locomotives, as part of the contract, Southern Pacific was to supply no car-bodies or shells. The rebuilds consisted of a total of thirty EMD SD40 units, ninety-seven EMD SD45 units and six EMD SDP45 units all of which from various other railroads. Morrison–Knudsen also made ten SD40M-2s for the Canadian Pacific Railway using seven SD45s and three SD40s.

SD40-2/SD40-3

The units are rebuilt with a 16-cylinder engine and derated the units from 3600 to 3000 HP.

SD45 operators

SD45X operators

Preservation