The DR-6 was a family of six-axle diesel-electric locomotives built by Baldwin for passenger service between 1945 and 1948. Most were of the type DR-6-4-2000, what means that they had six axles, four of which were powered and a total of 2,000 hp. The two demonstrators were powered by two of the old eight-cylinder 8VO engines. They had one cab and featured the babyface design. After these, production variants were offered with more modern engines and different gear ratios which offered a top speed between 65 and 120 mph (105 and 193 km/h).

Ten production locomotives were built with the babyface design for several customers. These were powered by two naturally-aspirated eight-cylinder 608NA engines which also had 1,000 hp each. Among these were six which had been built for the Central Railroad of New Jersey with cabs on both ends. The PRR ordered 18 A-units and 9 B-units which were designated class BP-20. These featured the sharknose design that was created by Raymond Loewy and could also be found on some later Baldwin diesels. On the BP-20, this design was supposed to look similar to the T1 steam locomotive. They were powered by the turbocharged six-cylinder 606SC engines, also with 1,000 hp each. Each train was hauled by a set of two A-units and a B-unit with a total output of 6,000, nearly as much as the T1.

Beside the 2,000 hp models, there were two lower-powered variants with only one engine. One was a single DR-6-2-1000 built for the Chicago & North Western. This had only one 1,000 hp 606SC engine in the front half and only the front truck was powered on two axles. In the rear half there was a baggage compartment for use with short local trains. The other single-engine variant was the DR-6-4-1500 that had a supercharged 608SC with 1,500 hp and a total of four traction motors. The New York Central had ordered four A-units and two B-units, while the Seaboard Air Line received three A-units.