Express locomotives were always the stars among steam locomotives by virtue of their power, elegance, and speed. The class 01 heavy express locomotive was probably for all intents and purposes the personification of the German standard design locomotive. It was reliable motive power for impressive express trains as well as for mundane passenger trains.
By 1938, a total of 231 class 01 locomotives had been produced by different German builders. In addition, there were also 10 class 02 locomotives rebuilt between 1937 and 1942 to the class 01. After World War II, 165 of the class 01 locomotives remained in the western occupation zone and 70 in the Soviet zone, of which several had to be retired due to extensive damage. Starting in the Fifties, both German railroads rebuilt their locomotives several times and adapted them to new uses by making use of technical progress. In West Germany, the large Wagner smoke deflectors were replaced by the small Witte versions, the compressor and feed water pump wandered on the DB locomotives from the niche on the smoke box to the center of the boiler, and the front skirting between the buffer beam and the running boards was removed on numerous units.
The class 01 was taken out of service on the DB in the middle of the Seventies; on the DR they lasted until the Eighties.