DC Direct current
DCT Dual clutch transmission
DDE Digital Diesel Electronics - diesel engine management system (Bosch)
DfT Department for Transport (UK)
DIN Deutsches Institut für Normung - German standards institute
DIS Direct ignition system or Distributorless ignition system
DLO Daylight opening
DME Digital Motor Electronics - petrol engine management system (Bosch)
DOHC Double overhead camshaft
DOT Department of Transport (UK DOT replaced by DfT)
DPF Diesel particulate filter
DRL Daytime running lights
DSC Dynamic stability control, also known as Electronic stability control
DSG Direct Shift Gearbox (Volkswagen)