[1] All were built in American Locomotive Company's plant at Schenectady, New York and were numbered from 450 to 470 as delivered.

Builders numbers 54568 through 54570 arrived in 1914 as sub-class C-2 with weight increased to 238,500 lb (108.2 tonnes).

Building of new 4-6-2s was interrupted by World War I when the United States Railroad Administration (USRA) authorized construction of non-standard class O 4-6-0s because Maine Central Pacifics were so much smaller than USRA Light Pacifics.

[1] The Budd Company Flying Yankee train set and unstreamlined 600 horsepower (450 kW) oil-electric rail car number 901 arrived in 1935.

EMD E7s numbered 705 through 711 began pulling main line passenger trains in 1946.