After the Cerro de Pasco Railway & Mining Co. had taken over the line between La Oroya and Cerro de Pasco in 1915, they needed powerful freight locomotives. Large parts of the line were situated at an altitude above 4,000 meters (13,123 feet), had inclines of 2.5 percent and curve radii of 110 m (360 feet). Over a total of 14 years, they received eight Consolidations from several ALCO works. The first two came from Brooks in 1916, followed by two from Cooke in 1919. Brooks again delivered two in 1925. The last two came from Schenectady in 1930, were oil-fired and had Worthington feedwater heaters. 

On the outside the different batches could be distinguished by details like the position of the domes, the headlight and the tubes on the outside of the boiler. They had received numbers between 1 and 8, six of which were re-used from earlier ones, so they were not in consecutive order. This explains why No. 8 shown in the photo was one of the locomotives built in 1919. Later they were renumbered 61 to 68.