The Class 01.5 with Boxpok Wheels
At the beginning of the Sixties, the GDR German State Railroad ran 35 units of the class 01 through an extensive rebuilding program. Initially, only the installation of a new welded "Reko" boiler was planned, the conservation status of the locomotives selected ultimately forced extensive rebuilding that resulted in the units becoming new locomotives in many respects. The maintenance facility in Halberstadt delivered the "Reko" boilers, and they were installed at the maintenance facility in Meiningen. During the rebuilding program the boiler was placed higher, continuous dome streamlining adorned the top of the boiler, and the cabs were replaced by a new welded version. The locomotives rebuilt in this way had hardly anything in common with their original look. After the rebuilding program, these units were therefore given the new class designation of 01.5. Beginning with road number 01 519 (rebuilt in 1964) the locomotives were equipped with oil firing, and the remaining units were converted accordingly in 1965/66. Only six locomotives kept grate type firing. Twelve units (01 502-504, 507-513, 517, and 518) at times were equipped with Boxpok wheels but the latter were swapped for reinforced spoked wheels at the latest by 1976. Road number 01 504 ran initially with a Giesl flat ejector. In addition, all of the units had a conical smoke box door without central locking after the rebuilding program. With the introduction of computer numbers, the coal-fired units became the class 01.15, and the DR designated the oil-fired units as the class 01.05.
After their rebuilding program, the locomotives were used in heavy express train service on the DR from Berlin East Station (grate-fired locomotives) as well as Wittenberge and Erfurt and also reached the West German turning points of Bebra and Hamburg-Altona in Inter Zone service up into the Seventies in regular schedules. These units were probably the most successful design of the class 01, and ultimately their career ended in 1982 in the Saale Valley. Five units of the class 01.5 were preserved and – to the extent they are still operational – still shake the rails in the East and West even after the reunification.