The EMD (Electro-Motive Division) SD70 is a type of six-axle, 16-cylinder, 4,000hp diesel locomotive built from
1993-1999 with 122 built specially for Conrail (CR), Illinois Central (IC), and Norfolk Southern (NS). Two were also built sold to the Southern Peru Copper Corporation (SPCC) for use in hauling copper ore trains, and are often paired with GP40-2 units.
Although the model was built nearly a year after the three SD70M demonstrators, it is often referred to as the "original" model, despite having originally been a catalog entry built upon request as a specialty model rather than a full-scale production model.
Many are still in service, though some have been scrapped or are currently stored awaiting service as spare units. All 24 of the original Conrail units are in service with NS, for they were built and numbered to NS specs prior to the Conrail merger in 1998, whereas Canadian National (CN) inherited all of the IC units (many are still left in their original paint). They have since become exceptionally rare to see, however.
With the ever-increasing success of the SD60 line, EMD stepped-up a notch to patent a radial, self-steering truck model. After numerous testing and evaluation dating back from 1984 to 1986 with ATSF GP50 #3810 and BN SDP45 6599, the final conclusion came with EMD #3: an SD60 demonstrator, retrofitted with the HTCR/HTCR-II truck model. The introduction of the revolutionary HTCR-II truck model not only returned EMD to its original innovative prominence, but also increased the tractive effort by 40-60% in contrast to the preceding SD60 and SD50 models. EMD and the host railroads found the results to be increasingly positive from what EMD #3 demonstrated, and in response to patenting the truck design or truck model, the SD70M debuted in 1992, while still offering a conventional-cab model within the builder's catalog. A year later, however, NS came knocking on EMD's door by ordering 56 units delivered between 1993-1994, for the wide-cab SD70M didn't quite meet their otherwise "ultra-conservative views". Illinois Central eventually caught on to the model, and for the first time in many years, acquired 40 units split into two separate orders in 1995 and 1999 (the latter half of units were assembled at Super Steel Schenectady). Conrail on the other-hand, received 24 SD70 units ordered by NS prior to the 1999 merger in the latter half of 1998, and were numbered NS #2557-2580 (with some bearing "PRR" initials stenciled under the numbers).
Besides the notable revolutionary truck design change, EMD insisted on updating the microprocessor control system and increasing the horsepower output from 3,800 to 4,000hp with an updated version of the existing 16-710G3 (known as the "16-710G3B") in a response to GE's ever-dominant C40-8 model. Unfortunately, the debut of the C44-9W in 1993 nearly spelled the end, for the lackluster sales of the SD70 and subsequent SD70M meant that AC-traction technology and cheaper alternatives from the competition meant the line was reaching it's unfortunate end. Though, wasn't until 1999 when Union Pacific (UP) placed a massive order of over 1,000 units; literally saving the DC-traction portion of the line (with the exception of the SD70I and subsequent SD75 models). However, as a result of the FRA's "Safety Cab" requirement for newly-manufactured locomotives built for Class 1 railroads effective in 1995, the so-called "original" SD70 model was ultimately discontinued from the primary market, and only offered for export, Class 2, or Class 3 production. However, NS bypassed the restrictions for the 24 Conrail units in 1998 as a result of the impending merger that was well underway in the following months, meaning that Conrail was merely a trademark or an entity rather than a Class 1 railroad. IC; being a Class 2 railroad, was excluded from said requirement.
Although very similar in appearance to an SD50 or SD60, the SD70 has a few distinct features that give its notable appearance:
- The first feature being the presence of the HTCR-II radial trucks as opposed to having "Flexicoil Type-C" (Flexicoil) or "HT-C" (HTC) trucks on previous models.
- A brake wheel or handbrake can be found located towards the rear of the long hood section of the carbody on the engineer's side.
- A small intake vent for cooling the traction motors can be seen on the opposite face of the handbrake on the conductor's side.
- Large, distinct bulge for housing the on-board microprocessor computer equipment located on engineer's side of the nose (front hood or short hood).
|Length||72' 4"||72' 4"||72' 4"|
|Weight x 1,000lbs.||394,000||398,000||390-400,000|
Note*: SD70M available for export beginning 2005.
|Conrail (CR)||24||Most in service with NS (some stored)||1997-1998|
|Illinois Central (IC)||40||Most in service with CN (some wrecked)||1995-1999|
|Norfolk Southern (NS)||56||Most in service with NS (some stored)||1993-1994|
|Southern Peru Copper Corporation (SPCC)||2||Both units in active service.||Unknown|
CN has utilized several of their IC SD70 units in DPU service by retrofitting them with the proper radio and microprocessor equipment. Said units can often be found with some of their C40-8 and C40-8M units.