Rebuilt into the 042 - In 1936 Schwarzkopff delivered the first fast class 41 freight locomotive. It turned out to be an extremely good general-purpose unit for medium heavy service and also worked well as motive power for passenger trains when required. By 1941 366 units had been build in a joint effort by almost all of the German locomotive builders. After World War II, 220 locomotives remained in West Germany and 142 in East Germany. Since the original boilers suffered increasingly from metal fatigue, the German Federal Railroad had a total of 99 (possibly 103?) units equipped with new, completely welded replacement boilers from 1957 to 1961. Other features on these units were changed in addition to the installation of fully welded, high-efficiency boilers. The running board skirting was cut back and along with other changes on the front part of the frame contributed to the typical look of these locomotives rebuilt by the DB. The DB converted 40 of the rebuilt class 41 units to oil firing and equipped them with an oil tender. From 1968 on these locomotives were designated the class 042. The new boiler itself led to an increase in power, and the installation of oil firing increased the potential power even more compared to coal firing. The oil fired 042 locomotives were based without exception in the Rheine District to the end of their service life in October of 1977. The association "Rendsburger Eisenbahnfreunde e.V." (Rendsburg Railroad Enthusiasts Society) took steps to maintain road number 042 271 in operational condition. In addition, road number 042 113, the last of this class retired by the DB, stands currently stands in the Auto + Technology Museum in Sinsheim, Germany.