In order to run ten-unit trains with a maximum speed of 160 km/h, four VT 11.5 were rebuilt in 1970 and received AVCO Lycoming TF55 gas turbines supplied under license by Klöckner-Humboldt-Deutz in place of their original Diesel engines. They were renumbered as Class 602 001–004 (ex-Class 601 nos. 012, 003, 007 and 010, respectively), recognizable at the large dimensioned air intakes, and used for DB InterCity service, starting with the train connection between Hamburg and Ludwigshafen in July 1974.
