The EMD F40PH diesel locomotive enters revenue service with Amtrak.

The EMD F40PH is a four-axle 3,000–3,200 hp (2.2–2.4 MW) B-B diesel-electric locomotive built by General Motors Electro-Motive Division in several variants from 1975 to 1992. Intended for use on Amtrak's short-haul passenger routes, it became the backbone of Amtrak's diesel fleet after the failure of the EMD SDP40F. The F40PH also found widespread use on commuter railroads in the United States and with Via Rail in Canada. Additional F40PH variants were manufactured by Morrison-Knudsen and MotivePower between 1988 and 1998, mostly rebuilt from older locomotives.

Amtrak retired its fleet of F40PHs in the early-2000s in favor of the GE Genesis, but the locomotive remains the mainstay of Via Rail's long-distance trains; a depiction of the locomotive hauling The Canadian is featured on the reverse of the Frontier series Canadian $10 bill. The F40PHs are still a common sight on many other commuter railroads throughout the United States. In addition, Amtrak has kept 22 of its F40PHs in use as non-powered control units.