EMD GP22ECO

The EMD GP22ECO is a 2,150 horsepower B-B diesel-electric locomotive rebuilt by Electro-Motive Diesel and, for Norfolk Southern, the railroad's Juniata Shops. EMD first built two demonstrators, one from a GP9 and one from a GP40, but later orders have been conversions of GP40 and GP40-2 locomotives. The rebuild replaces the prime mover with an EPA Tier II turbocharged V8 710G3A with electronic fuel injection, an AR10 alternator for traction power, a CA6 alternator for control power and a computerized control system. On GP40 and GP40-2 donors the conversion does not change the outward look. Applied to a six-axle locomotive it produces the SD22ECO, and some could instead become the 3,150 horsepower SD32ECO. Norfolk Southern's units were rebuilt from GP38AC locomotives.