THE EMD F40PH IS A FOUR-AXLE 3,000–3,200 HP 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.