<P> The drivetrain of a motor vehicle is the group of components that deliver power to the driving wheels . This excludes the engine or motor that generates the power . In contrast, the powertrain is considered to include both the engine or motor and the drivetrain . </P> <P> The market for drivetrain components is economically important and is estimated to reach US $314.4 billion by 2019 . Market value by layout is approximately half for front - wheel drive, with a quarter each for rear - wheel drive (mostly in light commercial vehicles and trucks) and all - wheel drive . </P>

What is the drive train on a bmw