SD70ACu Diesel Locomotive

Prototype Information

The EMD SD70ACU is a rebuilt locomotive based on former SD90MAC units. Norfolk Southern purchased 100 ex-Union Pacific SD90MACs in 2014 to handle high-volume traffic and embrace AC traction. Starting in 2016, NS began converting these units into SD70ACUs, overhauling or replacing all major components, including the 710G3C engine, electrical cabinet, and cab, which now features an ACe-style isolated cab with AAR-style controls.

Canadian Pacific followed with its own SD70ACU program, converting 60 former SD90MACs and a few ex-UP units starting in 2018. CP has painted several in special schemes, including Heritage Tuscan & Grey and military tribute designs. By 2020, all CP units were complete, operating across Canada, the U.S., and even reaching Mexico.

The SD70ACU represents a modern AC-traction freight locomotive built on proven SD90MAC cores, combining updated electronics, a comfortable cab, and reliable power for heavy freight service.