Railbus 998 751-2 (control car) of the DB – remote controlled clutch – The screw coupling can be retrofitted It was called the branch line rescuer, the red buzz or simply the Uerdinger railway coach, because most of the VT 98s were built in the Uerdinger wagon factory. They were powered by two 150 hp Büssing floor engines, the same engine as the Berlin double-decker buses. ZF Friedrichshafen AG contributed the six-speed gearbox. The VT 98 railcar was also accompanied by the VB 98 sidecar (some with luggage compartment) and the VS 98 control carriage. But shorter two-car VT+VS units and longer units with up to six cars were also used. In the late 1980s, the VT 98 (or 798, as it was called from 1968) was gradually replaced by the 628 series, which in turn had more modern successors such as t.