| American Locomotive Company
Montreal Locomotive Works|
April 1956 – March 1963
4 ft 8 ⁄2 in (1,435 mm) standard gauge
ALCO RSD-12 Wikipedia
The ALCO RSD-12 was a diesel-electric locomotive of the road switcher type rated at 1,800 horsepower (1.34 MW), that rode on three-axle trucks, having an C-C wheel arrangement.
Used in much the same manner as its four-axle counterpart, the ALCO RS-11, though the six-motor design allowed better tractive effort at lower speeds.