The popularity of the two “Glass Trains” ET 91 prompted the Reichsbahn to also order the diesel-powered panorama railcar 137 240 from Fuchs in Heidelberg. It had a similar structure to the ET 91 and was powered by two DWK boxer engines. The engines, along with some other aggregates, were mounted in an auxiliary frame to transmit less noise and vibrations to the passenger compartment. Thanks to the lack of roof equipment compared to the electric multiple unit, the roof was designed to be openable and the frame was reinforced to compensate the lower strength of the roof. The benches were designed with movable backrests so that the passengers could sit in both directions of travel.

Since the design made a good impression, two more examples with the numbers 137 462 and 137 463 were put into service in 1939. One vehicle did not survive the Second World War, the other two were taken over by the Bundesbahn as VT 90 500 and 501. They received new engines and brakes from 1953 and were based in Cologne and Stuttgart. From there they made excursions in a large area until they were retired in 1960 and 1962.