Looking to make its dollar go further, Metra turned to Progress Rail to convert former freight locomotives into passenger power for Chicago.
Over the past few years, Sean Cronin, Senior Director of Mechanical Projects for Metra, has received occasional inquiries from colleagues at other commuter agencies that can be summed up something like this: What’s the deal with those six-axle freight locomotives you’re using in passenger service?
There’s no denying that Metra’s fleet of SD70MACH locomotives is unusual. After all, it wasn’t long ago that they were leading freight trains for Kansas City Southern. However, three years after the first ones arrived in Chicago from Progress Rail, Metra officials said they are pleased with their freight-haulers-turned-commuter-cruisers. They are so pleased, in fact, that on June 18, Metra’s board of directors approved the acquisition of nine more units, bringing the total to 42.
“We are extremely happy with them,” Cronin said.
Metra’s search for new motive power began in 2017 when it issued a request for proposals to replace its aging fleet of mostly Electro-Motive Diesel F40s, which at that time averaged 30 years old. Some of those units even predated Metra—the brand created in 1984 to operate Chicago’s commuter rail system, the largest in the country outside of the New York metropolitan area—to 1977, when the Regional Transit Authority acquired its first F40s. In 2017, Metra committed about $125 million for locomotive purchases over the following five years, far short of what it needed to replace the entire fleet. “We’re trying to do the best we can with available resources,” said CEO and Executive Director James M. Derwinski at the time. “However, we need more capital dollars to continue to invest in our system and upgrade our assets.”
To maximize the budget, Metra’s RFP sought information on purchasing 12 new locomotives or 15 remanufactured ones, with options to eventually acquire a total of 42 units. Metra received several proposals, but the most intriguing came from Progress Rail, the Caterpillar subsidiary that purchased EMD in 2010. Progress Rail proposed rebuilding 15 SD70MAC locomotives into passenger units. The SD70MAC was introduced in 1993, and EMD built more than 1,100 of the six-axle AC units throughout the next decade. While the vast majority of the SD70MACs built were for freight service, the Alaska Railroad acquired 12 units that featured 480-volt head-end power (HEP) for use in both freight and passenger service. They were the only dual-service SD70MACs ever built.
But perhaps the most unusual aspect of the proposal was that the SD70MACs featured six axles, a rarity in modern passenger railroading. However, Metra had more experience with six-axle passenger locomotives than most. The agency was among the last in the country to utilize EMD’s famed E-units in the 1980s and 1990s, and as late as the 2010s, it rostered the unique F40C locomotive (only 15 were ever built, all for the former Milwaukee Road commuter lines operated by Metra). Undeterred by the quirks of a six-axle freight locomotive being rebuilt for passenger service, Metra’s board approved a $70.9 million contract in 2019 for 15 refurbished locomotives, designated the SD70MACH.
Tito Miglio, Senior Vice President of Locomotive Sales in North America for Progress Rail, said the idea of rebuilding SD70MACs for Metra made sense on several levels. First, Metra has traditionally preferred EMD locomotives (the only non-EMDs in the fleet are 27 MP36PH locomotives built by Motive Power Industries/Wabtec, though they use an EMD engine). Additionally, Metra’s commuter trains primarily operate on rail lines owned by Class I railroads (including BNSF, Union Pacific, CPKC, and CN), so it was clear that these former freight locomotives would have the necessary clearance to run on Metra.
“This is a type of locomotive that has operated on these lines for a number of years, long before Metra even considered them,” Miglio said.
While that is certainly true for the main line tracks, Cronin said Metra checked the geometry of all trackage the SD70MACs would operate on (including yard tracks) to ensure that nothing had changed in the years since E9s and F40Cs had operated on them.
The locomotives selected for the rebuild program had previously operated for Kansas City Southern de México (KCSM, formerly Transportación Ferroviaria Mexicana, or TFM). As part of the rebuild, the locomotives were regeared to reach 85 MPH to meet the maximum speed limit on the Metra system of 79 mph (most SD70MACs are geared for 70). Cronin said the locomotives were designed to match the acceleration and deceleration of Metra’s F40 fleet, ensuring that they could maintain the commuter railroad’s current schedule. The new units have also been outfitted with microprocessor-controlled braking from New York Air Brake.
The locomotives feature a B1-1B truck arrangement, which means that only the outer four axles are powered; the two axles nearest to the fuel tanks are unpowered. The inverters that would typically power these axles are instead utilized to generate HEP.
To ensure the locomotives would face no issues on any track operated by Metra, Progress Rail reduced the locomotives’ weight on rail to less than 210 tons, which is still significantly heavier than Metra’s other units (the F40s weigh between 132 and 132.5 tons, and the MP36PHs clock in at about 148 tons). To meet this target, Progress Rail decreased the fill capacity of the locomotive’s 4,900-gallon tank to 4,000 gallons.
Other improvements to the locomotives included cab signals, PTC (positive train control) and heated, illuminated walkways along the long hood. Miglio stated that the walkways were enhanced to allow train crews to easily walk between the locomotive’s cab and the rest of the train, similar to how they would on any other unit on the Metra roster (although this usually occurs within the locomotive carbody). The units comply with Tier 3 standards and are Metra’s first AC locomotives.
The first SD70MACH locomotives arrived in Chicago in late 2022 and began testing the following year. Since then, the locomotives have been primarily placed in service on Metra’s Milwaukee District North (Chicago to Fox Lake) and Milwaukee District West (Chicago to Elgin) lines. Cronin said eventually Metra would also like to assign the locomotives to the Rock Island (Chicago to Joliet) and BNSF lines (Chicago to Aurora).
Cronin noted that although there were initial problems with how the locomotives operated in winter—specifically, issues with snow ingestion affecting the locomotive’s electrical system—they have since become some of the best locomotives in the Metra fleet. He praised Progress Rail for its response to the few issues that have arisen. Train crews also like the locomotives and have said the SD70MACHs ride smoother and are significantly quieter than the older F40 locomotives. Additionally, the SD70MACHs have improved Metra’s operations by enabling more trips between fueling, thanks to the larger fuel tank. Cronin said that with 4,000 gallons of fuel, the new units can make almost twice as many trips as the older F40 units, which have fuel tanks that range from 1,800 to 2,000 gallons.
Following the initial order of 15 units, Metra’s contract with Progress Rail included three options for an additional 27 units (nine units in each option). With the decision on June 18 to exercise the third and final option, it is likely that Progress Rail will begin construction on the final nine SD70MACHs next year, with delivery expected through 2026 and 2027.
Metra officials said the SD70MACs provided the best value for the agency’s budget. This is especially important in an era of increasingly tight budgets, not only at Metra but also at public transit agencies nationwide. Whether other commuter railroads will follow Metra’s approach remains to be seen. Nevertheless, it could certainly be a compelling option, particularly given that the average age of a unit in the U.S. commuter rail fleet is 28 years.
“At the end of the day, it came down to price,” said Derwinski. “We’re essentially getting two units for the price of one.”
