The EMD E7 was the first model in the series built fully under the General Motors banner and went on as the most successful. The design began construction in early 1945 and was ultimately purchased by dozens of major railroads for use in passenger service. Internally, the E7 varied little from the E3 through E6 models. However, externally, EMD updated the carbody giving it a sleeker look and a more beveled, blunted nose (the classic "bull dog" appearance that made EMD's cab design legendary) that was first featured on the freight FT of 1939. Some E7s saw service for many years and were still around until the start of Amtrak in 1971. The succeeding E8 was also purchased by many railroad successful. Incredibly, despite more than 500 E7As and Bs constructed be Electro-Motive just one is preserved today, Pennsylvania #5901.
The EMD E7 began production in early 1945 as the first passenger model manufactured by GM's official Electo-Motive Division. The model's internal components were more or less similar to earlier models. While the locomotive did feature a slightly upgraded 12-cylinder, model 567A prime mover it still carried a rating of 2,000 horsepower (using dual engines). The truck setup remained the same as an A1A-A1A (meaning the center axle was unpowered) and model D7 traction motors. Finally, as had been the case for most E series designs cataloged by Electro-Motive through that time the E7 offered 56,500 pounds of starting tractive effort and 31,000 pounds continuous. Interestingly enough, there was no deviation from this rating all of the way through the E9.
By 1945 EMD's products were well known for their reliability, efficiency, and ruggedness. The builder paved the way for the fall of steam thanks to its FT, and then went on to silence the motive power forever with future models like the F7, GP7, GP9, and others. As such, most railroads came to trust Electro-Motive's products and were willing to use the E7 to power their most prestigious trains of the time. Numerous lines from the Baltimore & Ohio and Atlantic Coast Line to the Milwaukee Road and Southern Pacific purchased the streamlined diesel. While EMD's passenger line was never as successful as its freight models the builder sold some 428 E7As and 82 E7Bs by the time production had ended in the spring of 1949.
The reliability of Electro-Motive's E7 and later E models could been seen in their longevity. Many of those not traded in and replaced by the later E8 saw service up until Amtrak, although by that time with service in severe decline many units had been extremely abused and were simply worn out. It is not believed that any remaining E7s actually made it into service on Amtrak although the carrier did utilize a number of aging E8s, E9s, FL9s, and FP7s. Sadly, the Rock Island which could not afford to join Amtrak (railroads had to pay a fee to the carrier to hand over their remaining passenger trains) continued to use some of its worn out E7s in passenger service through the late 1970s.
As a comparison, the only other locomotive builder to truly compete in the passenger model market with EMD was Alco and its PA model. While considered the most beautiful diesel locomotive ever built, unfortunately it used a troublesome and unreliable prime mover that caused many railroads to stick with EMD, even after Alco corrected the issue with a new engine in the PA-2. As mentioned above, PRR #5901, is the only E7 still in existence. Today, the Pennsylvania unit remains cosmetically restored at the Railroad Museum of Pennsylvania in Strasburg and can be regularly visited by the public, housed in-doors and out of the elements.