What is today known as Electro-Motive Diesel has a history dating back
to the early 20th century. EMD originally began as the Electro-Motive
Corporation, a privately owned company being based out of Cleveland,
Ohio that built inexpensive motorcars beginning in 1922. With the
purchase of the company in 1930 by General Motors, 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.
A pair of Santa Fe GP30s led by #1203, as well as another EMD unit, roll past Joliet Union Station with a westbound freight during early September of 1962.
However, before this development and
new technology was introduced, EMC had already become part of General
Motors, having been purchased by the company in 1930 and branded GM's
Electro-Motive Division, a name it would hold for 75 years. Because the power cars with these trainsets were permanently attached to the coaches
EMD 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 EMD’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 many for the efficiencies
it held over steam such as its ruggedness and ease of maintenance. The FT 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
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 BL2 was certainly unmistakable with its longer nose and
recessed carbody, which allowed the cab to be much more “open” and train
crews could see behind the locomotive as well as to the front. Built
only between 1948 and 1949, the model came in the standard GP
configuration of four-axles and it carried 1,500 horsepower. A total of
59 BL2s were built, naturally making them very rare today! Having said
that, a number of them survive and at least two are still operational;
one, on the West Virginia Central in West Virginia and the other on The
Stourbridge Line in Pennsylvania.
The first of the GP series was the four-axle, GP7, which began
production in 1949. Still commonly found today on several regionals and
shortlines the GP7 is the classic image of the road switcher with its
high, short hood and cab set off to one end leaving for a long hood
trailing. The model was most commonly built with the high hood but some requested a lowered version in the later standard cab design,
which included front windshields (GP7s would also be rebuilt with
Two Burlington SD24s with #509 in the lead navigate through the weed-filled yard at St. Paul on June 19, 1964. The CB&Q went on to purchase sixteen examples of this early second-generation EMD design.
Through 1954 the model sold an astounding 2,600+ units and is widely
credited with completing main line dieselization, relegating most
remaining steam locomotives to branch line, yard and short line work (an
exception would be the Norfolk & Western, which held out on
scrapping its steam fleet until the late 1950s). Following the GP7 was the GP9, which saw an increase of 250 horsepower from 1,500 to 1,750. The model also blew away the GP7's staggering sales numbers, selling more than 6,000 units. Aside from the model's increased horsepower perhaps it's biggest improvement over the GP7 was the addition of dynamic brakes.
By the 1950s EMD was the unquestionable leader of diesel locomotive manufacturing, making up the vast majority of all diesel sales during that time. The company originally introduced a six-axle model of its popular GP series a few years after the GP7, in 1952. Known as the SD7 ("SD" stood for Special Duty), high-hooded models
were standard through the following SD9 and SD18 but these three types
never sold nearly as well as their four-axled brethren. However, that would change with the second-generation power as EMD's SD24 and subsequent models far outsold their four-axle counterparts. For more reading and information about all of EMD's locomotive models please click here. This was especially true when the company
debuted its SD40 series. Along with its "Dash 2" sister the SD40
series have become icons, even in their own time!
So successful was the
series that one can spot them virtually any place on practically any
given train (Class Is included), even today, over 20 years after the
last SD40-2 rolled off of the assembly line! The SD40 series began production in 1966 with the SD40, which was
built through 1972 and ended production in 1986 when the last SD40-2
rolled off of the assembly line. By the time production ended an
astronomical 5,200+ units had been built! Most of these were SD40-2s as
just under 4,000 were produced during its fourteen years of production
while the SD40 chipped in another 1,200+.
CSX SD70MAC #786 and a mate lead freight Q138 through McKeesport, Pennsylvania on April 10, 2005.
When the series debuted it was just what railroads were after. Looking
for a more powerful, reliable and gritty locomotive that could be
counted on to work properly in almost any type of weather conditions the
SD40 and SD40-2 were it. Rated at 3,000 hp, equipped with EMD’s
standard cab design, and a C-C layout (meaning they had six axles) the
units carried their builder’s 16-cylinder 645E3 diesel engine and high-traction truck. Extremely reliable the prime mover
was loved by maintenance and shop crews and even many engineers have
said the locomotive itself is a joy to operate as it experiences very
little problems when in service. This reliability, ruggedness, and ease of maintenance have
been so fantastic with the SD40 series that the units continue to not
only remain in common use on Class Is but also the big carriers have
liked them so well that many are rebuilding the locomotives to keep them
in active service for years to come!
However, following the SD40 series EMD's tight grip as the number
one manufacturer began to loosen. General Electric, which had entered
the market in the 1950s with its Universal series, following its breakup
with Alco (before this the two companies had worked together building
diesels), had slowly been gaining market share. When EMD introduced its
trouble-prone SD50 in 1980 it was already receiving increased
competition from GE, who had already put Alco out of business more than a
decade earlier, and the SD50 fallout only made things worse. By the mid-1980s GE had taken over the number one spot and has
retained it ever since. However, EMD found its footing again with its
SD70 and SD80 models, the former of which is still in production today
as the SD70ACe, a low-emissions main line locomotive.
UP's Chicago & North Western heritage unit, SD70ACe #1995, leads the business train through Pajaro, California on March 27, 2009.
The unit was originally introduced in 1992 but the latest version has only been available since 2005. It has sold well and today is Electo-Motive Diesel's primary unit for sale. Electro-Motive Diesel's biggest recent change occurred when the company was spun-off by General Motors in 2005 and once again became an independently owned and operated company. It continues to hold its own with GE and reliability has once again returned with its locomotives. Perhaps its biggest selling feature are the HTCR Radial trucks equipped on its locomotives, which steer into curves instead of simply following the track. The trucks greatly reduce wear to both locomotive and rail. Listed below are the various locomotive models and designs built by Electro-Motive Diesel.