Constructed between 1965 and 1971, the four-axle GP40 was one of the earliest EMD locomotives from the Second Generation era, and it continues to be found in operation today. An evolution of the previously offered GP35 series, the GP40 was designed with versatility in mind, being equally efficient at yard work, industrial operations, and light road duties. A staggering 1,221 units were produced for railroads across the United States, Canada, and Mexico, using mostly standardized components unless directed otherwise by the purchaser. On January 1st, 1972, the GP40 was succeeded by the GP40-2; a variation featuring a modular electrical system that would last in EMD's line for another 14 years. Despite being out of production for more than three decades, their reliability and ease of operation have continued to earn these iconic locomotives a place in modern railroading, and to date, a successor to their enduring design has yet to be established. | 
