In 1946, the L&C upgraded its fleet by buying six diesel locomotives from the U.S. Army. These 65-ton Whitcomb locomotives had seen service in Italy during the war and burned about the same amount of oil to run that the old steam engines used for lubrication. The purchase of these engines made the L&C the first fully diesel-operated railroad in the state, something that Springs liked to boast of. The steam engines formerly used by the railroad were either sold or put out to pasture. However, these diesels did not spend long on the line as they were replaced by three 70-ton GEs in late 1950. Among the Whitcombs, number 51 passed to the Allegheny and South Side Railway where it would stay until the end of that property.