EMD SD70 series


The EMD SD70 is a series of road switcher diesel-electric locomotives produced by Electro-Motive Diesel in response to the GE Dash 9-44CW. Production commenced in late 1992 and since then over 5,700 units have been produced; most of these are the SD70M and SD70MAC models. All locomotives of this series are hood units with C-C trucks, except the SD70ACe-P4 which has a B1-1B wheel configuration, and the SD70ACe-BB, which has a B-B-B-B wheel arrangement.
Superseding the HT-C truck, a new bolsterless radial HTCR truck was fitted to all EMD SD70s built 1992-2002; in 2003 the non-radial HTSC truck was made standard on the SD70ACe and SD70M-2 models; the radial HTCR truck remained available as an option.

Models

SD70 (1992-1994)

The EMD SD70 typically has the smaller spartan cab, typical on preceding SD60 models, instead of the larger comfort cab used on later models. Notable differences between the SD70 and SD60 are the radial steering EMD HTCR truck instead of the older HTC truck, and the SD70's overall length of 72 ft 4in, the older SD60 being 71 ft 2 in. The SD70 also rides higher as its frame is approximately higher than the SD60. This model is equipped with direct current traction motors, which simplifies the locomotive's electrical system by obviating the need for computer-controlled inverters. It is equipped with the, 16-cylinder EMD 710 prime mover. One hundred and twenty-two examples of this model locomotive were produced for Norfolk Southern Railway, Conrail, Illinois Central Railroad and Southern Peru Copper Corporation. Conrail's assets were split between Norfolk Southern and CSX Transportation in 1999, and all 24 of Conrail's SD70 units went to NS. Other than the CR paint scheme these units were built to NS specifications and numbered in series with Norfolk Southern's already purchased SD70s.
Production of the standard cab at EMDs London, Ontario plant ended in 1994. The 24 Conrail SD70s were assembled from kits at Conrail's Juniata Shops in Altoona, Pennsylvania, where the IC and SPCC SD70s were assembled from kits at Super Steel Schenectady. Most SD70s are still in service with Norfolk Southern and Canadian National, which merged Illinois Central in 1999. In February 2017, NS began a program to convert their SD70s from DC to AC, which will also have a new wide cab, and several other upgrades. They will be designated as SD70ACC.

SD70M (1992-2004)

The SD70M has a wide nose and a large comfort cab, allowing crew members to ride more comfortably inside of the locomotive than the older standard cab designs. There are two versions of this cab on SD70Ms: the Phase 1 cab, which was first introduced on the SD60M, and the Phase 2 cab, which is a boxier design similar to the original three-piece windscreen on the SD60M, which is shared with the Phase 2 SD90MAC, SD89MAC, and SD80ACe. The Phase 2 cab has a two-piece windscreen like the Phase 1 windscreen but the design of the nose is more boxy, with a taller square midsection for more headroom.
The SD70M is equipped with D90TR DC traction motors and the 710G3B prime mover. They are capable of generating of continuous tractive effort. From mid-2000, the SD70M was produced with SD45-style flared radiators allowing for the larger radiator cores needed for split-cooling. Split-cooling is a feature that separates the coolant circuit for the prime mover and the circuit for the air pumps and turbocharger. There are two versions of this radiator: the older version has two large radiator panels on each side, and the newer version has four square panels on each side. This modification was made in response to the enactment of the United States Environmental Protection Agency's Tier 1 environmental regulations. Also the truck was replaced with HTCR-4, instead of HTCR-I on former model.
Production of the SD70M ceased in late 2004 as production of the SD70M-2 model began. 1,609 examples of the SD70M model were produced. Purchasers included CSXT, New York Susquehanna & Western, Norfolk Southern and Southern Pacific, but the vast majority were purchased by Union Pacific.
An order of SD70Ms made history when Union Pacific ordered 1000 units of the model. This order was later extended by nearly 500 additional units.
This locomotive model is also built for export, and is still catalogued by EMD. CVG Ferrominera Orinoco has 6 SD70Ms that were built as an add-on order to UPs FIRE cab equipped SD70Ms. Companhia Vale do Rio Doce in Brazil has ordered 55 of this model for service in Carajas pulling trainloads of iron ore. Since CVRD track is gauged at, a wider bogie, the HTSC2, was designed for these units by EMD.

SD70I (1995)

The SD70I is a version of the SD70M which has been fitted with a cab that is isolated from the frame of the locomotive with rubber gaskets. The isolation reduces noise and vibration from the prime mover. A seam is visible across the nose and on the long hood where the cab connects with the body. 26 examples of this model locomotive were produced, all for Canadian National Railway. The WhisperCab feature was incorporated into some SD70MACs and was standard on both the SD80MAC and SD90/43MAC models.

SD70MAC (1993-2000)

The SD70MAC uses three phase AC traction motors. Production of the model commenced in 1993, competing against the GE Dash 9-44CW. The majority of SD70MAC models were produced with the EMD 710 prime mover while later units are rated at and feature EMD SD45-style flared radiators. The Alaska Railroad ordered their locomotives with head-end power to make them suitable for both freight and passenger service; no other railroad ordered this variant. The trucks were replaced with HTCR-4, instead of HTCR-I on former model.
-style flared radiators leading a stack train.
The SD70MAC is no longer produced due to EPA regulations, and was replaced by the SD70ACe in 2004. In total, 1,109 SD70MACs were produced, purchased by Burlington Northern Railroad, Conrail, CSX Transportation, Transportación Ferroviaria Mexicana, and the Alaska Railroad.

SD70ACe (2004-2015)

The SD70ACe is the successor to the SD70MAC with design changes to comply with emission standards. The engine fires with 15% lower internal pressure to improve emissions and features fewer internal components in the inverter. SD70ACe is equipped with EMD's 16-710-G3C-T2 prime mover, rated at ; later Tier 3 models are rated at. They are rated at continuous tractive effort. Braking effort is rated at.
In 2012, EMD also built four models known as the SD70ACe-P6. These units, unlike previous SD70ACe's, have one inverter per axle on the trucks, rather than EMD's traditional one inverter per truck design.
In 2014, BNSF Railway took delivery of 20 SD70ACe-P4 units, numbered 8500-8519. This model was designed with a B1-1B wheel arrangement to compete with GE's ES44C4 model, which has an A1A-A1A wheel arrangement. Two of EMD's demonstrator SD70ACe-P4's went to Tacoma Rail in late 2014 for a 5-year lease.
On January 1, 2015, the United States Environmental Protection Agency's Tier 4 locomotive emission regulations went into effect. EMD could not successfully modify the SD70ACe's 2-stroke 710 series prime mover to be Tier 4-compliant; thus, the Tier 3 SD70ACe was succeeded by the SD70ACe-T4 in late 2015. However, US production of the Tier 3-compliant SD70ACe continues with Tier 4 'credit units'. Union Pacific and Norfolk Southern are currently the only US roads to own Tier 4 credit unit SD70ACe's. Additionally, EMD has continued building Tier 3 SD70ACe's for Ferromex, Ferrosur, and Kansas City Southern de Mexico at Bombardier's locomotive plant in Ciudad Sahagún, Mexico. These locomotives are restricted to Mexico-only operation and cannot cross the US border.
In March 2016, EMD replaced the standard cast HTCR-4 trucks on NS SD70ACe 1000 with the new fabricated HTCR-6 trucks for testing. UP and BNSF plan to test the new HTCR-6 trucks on some of their SD70ACe units also.
Union Pacific Railroad received 273 additional SD70ACe units in 2014 and 2016. These are referred to as SD70AH , H for Heavy, because they are ballasted to 428,000 lbs instead of the standard "ACe's" 420,000 lbs.

SD70M-2 (2004-2011)

The SD70M-2 is a DC traction version of the SD70ACe, and is nearly identical to the SD70ACe. Production began in 2005. SD70M-2 models are equipped with the 16-710G3C-T2 or 16-710G3C prime mover which is rated at.

SD70ACe-T4 (2015-present)

The SD70ACe-T4 is the Tier 4 emissions standards-compliant successor of the SD70ACe. The first locomotive, EMDX 1501, was built in summer 2015, and made its debut at the Railway Interchange Expo in Minneapolis, Minnesota during the weekend of October 3–4, 2015. It features a new 4-stroke engine called the EMD 12-1010 "J" series - a V12 with 1010 cu.in displacement for each cylinder. This new prime mover has a two-stage turbocharger system consisting of three turbos; one turbo for low-mid RPM and two turbos for mid-high RPM. The results of this setup are higher power throughout a broader RPM range, better fuel efficiency, and lower emissions. An EGR system is applied as well, allowing the engine to achieve Tier 4 without the use of urea aftertreatment. Another new feature of this engine is the Double-Walled Fuel Injection System that increases safety and provides simplified maintenance works.
The EMD 12-1010 is capable of producing 4,600 hp, but only 4,400 tractive horsepower. With a new computer software for the on-board computer and one inverter per axle - unlike most of previous EMD locomotives that use one inverter per truck, the SD70ACe-T4 is capable of generating 200,000 lbf. of starting tractive effort, and 175,000 lbf. of continuous tractive effort. Meanwhile, its dynamic braking effort is as much as 105,000 lbf. The amount of starting tractive effort is equal to that of the 6,000 hp SD90MAC-H while, on the other hand, its continuous tractive effort is higher than that of the SD90MAC-H. The units are also equipped with "radial bogies" which offer increased adhesion and better ride quality.
While it retains the basic SD70 designation, the locomotive has several major new features that set it apart from its successful ancestor such as a vibration-isolated powertrain, and alternator start capability. In addition, it features a newly redesigned cab reminiscent of the earlier SD70M, featuring the classic "teardrop" windshields first introduced on the FP45 in December 1967; new fabricated trucks; a longer frame ; longer radiators with three radiator fans instead of two; an additional step on the front and rear; and a smoother long hood roofline.
Fifteen SD70ACe-T4 demonstrators were built at Muncie, IN by November 2016. Union Pacific Railroad is the first customer to order SD70ACe-T4's. UP 3012-3014, the first production SD70ACe-T4's, were assigned to active service in early November 2016.
Union Pacific will acquire 100 SD70ACe-T4's: 12 former demonstrators will be rostered as UP 3000-3011, and 88 production units. 3012-3056 were built at Bombardier's Sahagun, Mexico plant. 3057-3099 will be built at Muncie, IN, following completion of the Tier 4 credit SD70ACe's UP 8997-9096. All UP SD70ACe-T4's are classified as SD70AHT4s.
EMDX 1501 will remain in Progress Rail Services ownership as a test bed.
SD70ACeP4-T4's EMDX 1603 and 1604 were built and painted as demonstrators for the BNSF Railway. These units have a B1-1B wheel arrangement akin to the SD70ACe-P4.
In August 2018, CSX Transportation ordered 10 SD70ACe-T4's, of which all have now been delivered. They are classified by CSX as ST70AH. Norfolk Southern initially ordered 10 SD70ACe-T4's, but later cancelled the order, instead opting for more SD70ACe Tier-4 credit locomotives. The cancelled SD70ACe-T4 locomotives are now part of the Progress Rail lease fleet.

SD70ACe/LCi (2005-Present)

The SD70ACe/LCi is a low clearance, export version of the SD70ACe. The LCi in the model designation stands for Low Clearance international as these locomotives are designed to negotiate the tight clearances under the mine equipment. External differences between the SD70ACe and SD70ACe/LCi models include the addition of marker lights, number boards located lower on the nose rather than on top of the cab, windscreen protector panels, fire suppression canisters, louvre style vents, different horn and subtle differences with handrails.
In 2004, BHP Billiton ordered a first batch of 14 SD70ACe/LCi locomotives for use on iron ore trains in the Pilbara region of Western Australia. It operated in 2015 a fleet of 23 SD70ACe/LCi locomotives beside of 142 standard SD70ACe, from which the newest locomotives are built in 2014.
The first member of the class was purchased for parts and dismantled upon arrival in Australia. This was because it was cheaper to purchase a complete locomotive than buy the components individually. The first batch of SD70ACe/LCi's was ordered in 2004 and named after sidings on the BHP system. Since it did not have the newer, isolated cab of the second and subsequent batches it was traded in to the supplier for locomotives with newer cab assemblies.
The second batch of locomotives arrived between August and November 2006.
An order for a third batch of 13 SD70ACe/LCi's was placed in August 2007, but such was the demand for locomotive power in the Pilbara region, a deal was done with BNSF Railway for BHP Billiton to purchase ten standard North American SD70ACes that were in build as their 9166, 9167, 9184-9191. Construction was sufficiently advanced when the deal was concluded for them to have been painted, hence they were delivered in BNSF orange livery. Some modifications have been made to bring them in line with the rest of the fleet. A fifth batch of SD70ACe's was delivered in July 2009.
An additional 18 units were delivered in the second half of 2010, bringing the total of SD70ACe type locomotives in service to 72. In March 2012, BHP Billiton ordered a further 80.
In July 2012 fellow Pilbara operator, Fortescue Metals Group, took the delivery of the first of a fleet of 19, later extended to 21.
In 2018, some BHP SD70ACe/LCis were sold to Montana Rail Link.

SD70ACS (2009-Present)

The SD70ACS is a AC variant for heavy haul freight, used in desert environments. The first 25 units were ordered for Saudi Railway Company in April 2009 and assembled in the London, Ontario plant for delivery in the second half of 2010. Special features include a pulse filtration system, movable sand plows, EM2000 control system and FIRE display system.
Mauritania's Société Nationale Industrielle et Minière placed a contract for six SD70ACS locomotives in October 2010.
In July 2011 Etihad Rail ordered seven SD70ACS locomotives for delivery in 2012. Seven locomotives were delivered in 2013.

SD70ACe-BB (2015-present)

In October 2015, EMD started producing SD70ACe-BB locomotives for Brazilian 1000mm gauge railroads.

SD70ACe/45 (2004-present)

The SD70ACe/45 is a diesel-electric locomotive built by EMD plant in Sete Lagoas, MG Brazil. Different from the SD70ACe in North America, the SD70ACe/45 has a longer frame and three radiator fans on the radiator section since it uses the same car body of the SD80ACe produced by EMD plant in London, Canada to Vale mining in Brazil. It uses gauge. 80 SD70ACe/45s had been built.

SD70IAC (2019-present)

In early 2019 with the delivery of the new SD70ACe-T4C locomotives to Norfolk Southern, a new type of the T4C locomotives was rolled out of Progress Rail in Muncie, Indiana. The SD70IAC, SD standing for Special Duty, 70 standing for 70 series, and IAC standing for Individual Axle Control. They are still classified as SD70ACe's on the side of the locomotive but are designated as SD70IAC within the cab controls. The new IAC system improves the existing traction system.

SD70ACe/LW (2007-present)

The SD70ACe/LW is a diesel-electric locomotive built by EMD. Similar to the SD70ACe in North America in the rear, it features a new isolated cab similar to the flat nosed cab of the GT46-ACE GEN II. The SD70ACe/LW has a 16-710G3C-T2 prime-mover with 4,500 horsepower. It uses an AC traction system with a top speed of 74 mph. The SD70ACe/LW is 16 feet and 6 inches tall With 1520 mm gauge.

Rebuilds

SD70ACU

The SD70ACU was first built by EMD and later rebuilt by Norfolk Southern. It is originally an SD90MAC that has been rebuilt to renew its electrical components and replace the cab with the new EMD Phase-II cab to comply with the most recent safety requirements. These locomotives are similar to the SD70ACe model, but the main body features are all reminiscent to the SD90MAC features. They also have the latest EMD cab that meets current FRA crashworthiness standards. These locomotives also have the Ultra Cab II, locomotive speed limiter, and cab signals. 100 of the 110 units Norfolk Southern purchased were originally SD9043MACs previously operated by the Union Pacific Railroad. The other 10 units were acquired by a trade with Cit Group for MP15DCs. All NS-owned SD9043MACs are slowly being rebuilt by NS at its shops in Altoona, Pennsylvania. As of May 7, 2019, all 110 SD70ACU units owned by Norfolk Southern have been completed and released to active service.
Canadian Pacific has also began a program to convert their SD90MAC units into SD70ACUs, but unlike Norfolk Southern, Progress Rail is performing the rebuilds. The first of these have since been released. The initial order was for 30 units and then increased to 60. Canadian Pacific originally rostered 61 SD90MACs, These units spent much of the 2010-decade parked in long term storage, with the exception of three, which were retired and scrapped in 2012. The remaining 58, along with two surplus Union Pacific SD90MACs, will be used as cores for the 60 SD70ACUs. 10 have been painted in the classic CP tuscan and grey paint scheme, and 5 as special armed forces units. The remainder will receive the standard CP red paint scheme.

SD70ACC

The SD70ACC is the latest rebuild in Norfolk's Southern's DC to AC program. It has the new EMD safety cab, similar to the SD70ACe cab, but with the “teardrop windshield”, much like the SD70ACe-T4. The SD70ACC has been rebuilt with AC traction motors, an AAR-style control stand, an electrical cabinet with Mitsubishi electronics, a new main alternator, and additional weight to increase the maximum weight to 432,000 pounds. The SD70ACC is rated at 4,500 horsepower, has a fuel capacity of 4,900 gallons, and has dynamic braking, cab signals, and LSL.
Norfolk Southern is rebuilding its fleet of SD70s into SD70ACC specifications. The first two units, 1800 and 1801, were unveiled in a special yellow and grey paint scheme to promote the DC to AC program, similar to the paint schemes used on the first GE AC44C6M. As of January 2020, 52 units have been rebuilt and have since been released to service, with many more units undergoing rebuild.

SD70MACe

The SD70MACe is a rebuilt SD70MAC locomotive with Electronics, first rebuilt by the BNSF Railway, and later rebuilt by CSX and KCS.

SD70MACH

The SD70MACH is a SD70MAC rebuilt by Progress Rail for Metra. The rebuild also includes the addition of head end power along with meeting Tier 3 emissions. Metra has approved of a purchase of 15 SD70MACHs for passenger service, with options of up to 27 more. They will become the first six-axle passenger engines since the EMD F40C and the Alaska Railroad's HEP-equipped SD70MACs.

Operators

North America

On November 8, 2019, Union Pacific donated SD70ACe #4141 to the George H.W. Bush Presidential Library and Museum. The locomotive, painted in honor of George H. W. Bush, was unveiled in October 2005 and was in active service until 2009, when it was placed into storage due to the financial crisis of 2007–2010, although it was brought back to participate in Bush's funeral train on December 6, 2018. It subsequently remained in active service following the funeral until its last run between November 8 and November 9, as part of the Union Pacific 4014 Southwest Tour, in which the plans for the display were unveiled. The 4141 exhibit is expected to open sometime in 2020.

Gallery

Footnotes