Diesel locomotive Calabro Lucane in southern Italy in 1926, following trials in 1924-5. In 1924, two diesel–electric locomotives were taken in service by the Soviet railways, almost at one time: In 1935, Krauss-Maffei, MAN and Voith built the first diesel–hydraulic locomotive, called V 140, in Germany. The German railways (DRG) being very pleased with the performance of that engine, diesel–hydraulics became the mainstream in diesel locomotives in Germany. Serial production of diesel locomotives in Germany began after World War II. In many railway stations and industrial compounds, steam shunters had to be kept hot during lots of breaks between scattered short tasks.
Diesel locomotive use. The first milestone in that effort was delivery in early 1934 of the Winton 201A, a two-stroke, Roots-blown, uniflow-scavenged, unit-injected diesel engine that could deliver the required performance for a fast, lightweight passenger train. The second milestone, and the one that got American railroads moving towards diesel, was the 1938 delivery of GM's Model 567 engine that was designed specifically for locomotive use, bringing a fivefold increase in life of some mechanical parts and showing its potential for meeting the rigors of freight service. Diesel–electric railroad locomotion entered mainline service when the Burlington Railroad and Union Pacific used custom-built