The engines are computer controlled, with the computer stopping and starting engines on a rotating basis, as required to produce the horsepower needed at any given moment.[1]
It has six-wheel (three-axle) trucks, rather than the usual four-wheel (two-axle) trucks commonly found on smaller, lighter, switcher locomotives. RP20CDs are rebuilt from older locomotives and can be upgraded to 2,700 horsepower (2.01 MW) by adding a fourth generator.[2]
