GP40-2 Boston & Maine #300PROTOTYPE SPECIFIC INFORMATION By the early 1970s, many first generation diesels were reaching the end of their service lives. The most common replacement locomotives became the GP40 2. EMD began production of the 16 cylinder, turbocharged, 3000 horsepower engine in 1972. These locomotive were developed for service where higher horsepower and faster service were preferable. A major feature for the GP40 2 was the introduction of the dash 2 modular