U25B Diesel Locomotive

Prototype Information

General Electric introduced the U25B in 1959, marking its serious entry into the domestic road locomotive market. Known as the first “Universal” series model, it featured a 2,500-horsepower FDL-16 engine. This was significantly more powerful than competing four-axle units of the time. Its sleek, low-nose design and simplified electrical systems set a new industry standard.

The U25B used a unique pressurized carbody to keep internal components clean and cool. This innovation reduced maintenance and improved reliability in harsh environments. Many major railroads, including the Pennsylvania and Southern Pacific, purchased the model to speed up freight schedules. While production ended in 1966, the U25B successfully broke the EMD monopoly and established GE as a major locomotive builder.