The GP50 and GP60, End of the "Geeps"

EMD originally began as the Electro-Motive Corporation and has its beginnings in 1922 being based out of Cleveland, Ohio building inexpensive motorcars. With the purchase of the company in 1930 by General Motor, and more resources at its disposal the company began developing the precursor of the modern-day diesel-electric road unit (cabs and road-switchers), the streamlined trainset, which consisted of a powered car permanently attached to a few coaches (usually two or three cars).

The most famous of these streamlined trainsets was the Burlington Zephyrs, a beautiful streamlined stainless steel creation (originally powered by Winton engines, which would also become a subsidiary of GM) that was extremely lightweight and fast. The original trainset, the Zephyr 9900, made headlines in 1934 when it completed a non-stop journey from Denver to Chicago in a little over 13 hours.

Because the power cars with these trainsets were permanently attached to the coaches EMC sought to design a locomotive free of this articulated setup but designed in such a manner that a railroad could still attach it to any passenger train and obtain the same, smooth streamlined look. This it did with the unveiling of the EA model in 1937, the first in a long line of passenger diesel locomotive designs that would come to be known as the E series.

Not surprisingly, soon after the EA unveiling the company decided to take things a step further and develop the first true diesel road unit, capable of pulling long freights in main line service. In 1939 it introduced the FT model (perhaps the key difference between the E and F series was that Fs rode on B-B trucks whereas Es rode on C-Cs and carried a noticeably longer carbody), the first in EMC’s F series and one of the most success diesel-electric designs of all time. The F series would go on to define American railroading for years and you can still see it in regular use today, over 60 years after it first debuted! The FT (which stood for Freight, Twenty-seven hundred horsepower) was a superb locomotive and although its 2,700 horsepower came from an A-B setup of a cab (A) and booster (B) units rated at 1,350 horsepower each, it was quickly loved by railroads for the efficiencies it held over steam such as its ruggedness and ease of maintenance.

The FT (which stood for Freight, Twenty-seven hundred horsepower) was a serious locomotive and although its 2,700 horsepower came from an A-B setup of cab (A) and booster (B) units rated at 1,350 horsepower each it would become embraced by the rail industry for the efficiencies it held over steam power as well as being rugged and easy to maintain.

Following the success of its cab units, EMD realized that there was a market to be made in the road-switchers, which at the time was mostly dominated by Alco with its RS series. Its first attempt at this type of locomotive, which gave the train crews both excellent vision all around the locomotive for switching and local service as well as enough horsepower to be used in main line operations, was the BL2. Although unsuccessful from a sales standpoint the BL2 was really a mere stepping-stone for its next model, the GP series (meaning General Purpose).

The GP50 and GP60 models all but ended the run of four-axle road-switchers for EMD. By the time the GP50 debuted in 1980 railroads were much more interested in six-axle power because of their advantages. For instance, with the two extra axles the locomotive’s weight was more evenly distributed over the rails causing less wear on them and it also allowed for increased traction with more axles in contact with the rail. By the time production ended on the GP60 in the mid-1990s sales were well short of earlier models like the GP40, GP40-2, GP38 and GP38-2. The GP50, built between 1980 and 1985 sold 275 units and the GP60, built between 1985 and 1994 sold slightly more, at a little over 350 units.

The GP50 and GP60 models, like GP40s and GP40-2s, are all built from the body and frame of the GP38 series. Like the GP40 series the most significant difference in the GP50 and ’60 were upgraded components (like a turbocharger silencer and new type of blower housing) and increased horsepower (the GP50 was rated at 3,500 hp and the GP60 at 3,800 hp). They also included features already common on earlier models such as dynamic braking (a system for temporarily employing traction motors as generators and using the resulting electromotive force to slow the train), and an airtight hood that kept out dust, dirt and other particles from reaching internal components.

Interestingly there was also a GP59 model cataloged by EMD built between 1985 and 1989. At only 12-cylinders compared to the standard 16-cylinders, the unit was rated at 3,000 hp. Virtually all were purchased by Norfolk Southern and save for one, the fleet remains in active service for the railroad. Perhaps the most famous of the units is #4610 which was commissioned by NS to commemorate the Southern Railway and is adorned in the predecessor’s beautiful green, white and gold livery. #4610 typically remains in service on NS’s southern lines so be on the lookout for it.

While the GP50 and GP60 models were not considered a success railroads could count on their reliability and dependability, which EMD is legendary for. In any event, with the models still relatively young they remain in service all across the country so be on the lookout for them, there are still many roaming around out there!

For more information on the GP50 and GP60 series consider Mike Schafer’s Vintage Diesel Locomotives, which looks at virtually all of the classic builders and models from Alco PAs to early EMD Geeps. If you’re interested in classic EMDs, or diesels in general, this book gives an excellent general history of both.

Also, Brian Solomon’s The American Diesel Locomotive also studies many of the same diesel models and builders as Mr. Schafer’s publication although at nearly twice the size the book goes into a bit more detail than Vintage Diesel Locomotives and also covers newer models. All in all, though, both books are a great read and you shouldn’t be disappointed with them, not to mention that they are loaded with photos (many in color)! If you're interested in perhaps purchasing these books please visit The Railroad Diamond by clicking the tab in the menu to your left marked "TRD Store".