The ALCO RSD-5 is a diesel-electric locomotive rated at 1600 hp, that rode on a pair of three-axle trucks, having a C-C wheel arrangement. Basically an upgraded version of the earlier ALCO RSD-4, and used in much the same manner as its four-axle counterpart, the ALCO RS-3, the six-motor design allowed better tractive effort at lower speeds.

Original owners

Preserved units

As of 2024, there are only two unrebuilt RSD-5s known to be in existence. • CNW #1689 is preserved and operational at the Illinois Railway Museum. • Utah Railway #306 is preserved at the Utah State Railroad Museum awaiting a planned restoration to its Utah Railway colors. It is currently painted as Nickel Plate Road #324, from its former owner, Doyle McCormack of the Oregon Rail Heritage Foundation. Two former RSD-5s (rebuilt as RSD-12's) built for the Southern Pacific survive at the Orange Empire Railway Museum (SP #2954 and SP #2958).