The C&O class T-1 was an important step in Lima's “super power” concept. It was a class of 2-10-4 “Texas” freight locomotives based on the 2-8-4 “Berkshires”, but with an additional driving axle. The idea came when the C&O borrowed a Berkshire from the Erie and thought that they needed to increase its power and tractive effort. The result were 40 locomotives numbered 3000 to 3039, which were built by Lima in 1930 with the works numbers 7516 to 7555.