In 1943, the heavy war locomotive of the series 42 was developed with a axle load of 17 tons. It was intended for use in Austria, but also in occupied areas where the track structure allowed it. The plan to build 8,000 locomotives (later reduced to 5,000) was halted by the end of the war, and ultimately just over 860 units were produced. The locomotives were used by the DB until 1960 and by the DR until around 1970.