EMD SD70ACu

EMD SD70ACu
NS 7248, one of the first SD70ACu models, sits outside the shops at Altoona, PA.
Type and origin Power type Diesel-electric Builder Electro-Motive Diesel/Norfolk Southern Model EMD SD70ACu Build date 2015-present Rebuilder Norfolk Southern
Specifications Configuration: ​  • AAR C-C  • UIC Co′Co′ Gauge 4 ft 8 1⁄2 in (1,435 mm) standard gauge Trucks EMD Radial Steering Wheel diameter 42 in (1,067 mm) Length 80 ft 2 in (24.43 m) Width 10 ft 2 in (3.10 m) Fuel capacity 4.700 gallons Prime mover EMD 16-710 G3B Engine type V16 diesel engine Aspiration Turbocharged Cylinders 16
Performance figures Maximum speed 75 MPH Power output 4,300–4,500 hp (3,207–3,356 kW)
Career Operators Norfolk Southern Locale North America Current owner Norfolk Southern Disposition Several units currently in rebuild process with 72 completed as of May 21, 2017

The EMD SD70ACu is a 6-axle 4,300–4,500 hp (3,207–3,356 kW) diesel-electric locomotive originally built by EMD, and rebuilt by Norfolk Southern at its shops in Altoona, Pennsylvania. The first locomotive entered the rebuilding process in September 2015, which was the 7299. 60 of these locomotives are now in service as of March 2017. They are currently being rebuilt from the SD90MAC's.

All of the SD70ACus will be rebuilt with the latest EMD cab which meets current FRA crashworthiness standards. The Siemens electronics will be replaced with Mitsubishi electronics. The rebuild also includes the installation of Ultra Cab II, locomotive speed limiter (LSL), and cab signals. The trucks will be rebuilt only as-needed and they are not getting traction motors swapped out.

The units that will be rebuilt are all ex-Union Pacific EMD SD90MAC locomotives. The SD90MAC was introduced in 1995 and was designed to use the new 16-cylinder, 6,000-horsepower (4,500 kW) H-engine. However, technical problems with the 265 engine resulted in the locomotives being delivered with the 4,300 hp (3,210 kW) 16-cylinder 710G used in EMD's SD70MAC. UP referred to these locomotives as SD9043MACs, and EMD planned to offer customers the option to upgrade them to the 6,000 hp (4,470 kW) 265 engine at a later date. EMD's upgrade program, however, was never carried out due to unresolved reliability issues with the 265. Over 400 SD90MAC locomotives fitted with the 4,300 hp (3,210 kW) 710 engine were built. 100 units originally ordered by Union Pacific were sold to Norfolk Southern as part of the SD70ACu rebuild program. EMD is responsible for delivering the locomotives, and as of November 2015, all units have been delivered. They are numbered 7229-7328. In July 2016, Norfolk Southern acquired another 10 SD90MAC locomotives from CIT Financial and the Indiana Railroad for the SD70ACu program. They will be numbered 7329-7338.