The DSE used 120-T and 030-T tank engines. Later in the 19th century, the PLM used 120 and 030 Bourbonnais, some of which were still in service in Bourg in 1950. But these locos were not powerful enough for the steep grade; most trains had to be double headed. Later and up until the second war, 140B, 140F, 230A came in. After the war 140L and 140J were used. The last was scrapped in 1961. The 141Rs so prevalent on the SNCF network, saw no service on the Haut-Bugey line as their axle weight was too heavy for the rails, although they did exceptionally run up to Nantua on trains unloading rubble from the Cret d'Eau tunnel.