For: Drivetrain (album) In a motor vehicle, the term powertrain or powerplant refers to the group of components that generate power and deliver it to the road surface, water, or air. This includes the engine, transmission, driveshafts, differentials, and the final drive (drive wheels, continuous track like with tanks or Caterpillar tractors, propeller, etc.). Sometimes "powertrain" is used to refer to simply the engine and transmission, including the other components only if they are integral to the transmission. In a carriage or wagon, running gear designates the wheels and axles in distinction from the body.

A motor vehicle's driveline consists of the parts of the drivetrain excluding the engine and transmission. It is the portion of a vehicle, after the transmission, that changes depending on whether a vehicle is front-wheel drive, rear-wheel drive, or four-wheel drive.

In a wider sense, the power-train includes all of its components to transform chemical, physical or nuclear energy into secondary energy and deliver it to the interface to the outer world for propulsion purposes. This includes the utilization of multiple power sources and non–wheel-based vehicles.

Developments

Powertrain development for diesel engines involves the following trends: modular injection, electronic valve control (EVC), low pressure exhaust gas recirculation (EGR), and advanced combustion. Spark ignition technology has focused on de-throttling (in part load where the low efficiency of Otto engines is defined) and downsizing (lower displacement, EVC).

Attention to new fuel qualities (no sulphur and aromates) allow new combustion concepts. These promise to combine clean combustion with high efficiency. So-called "combined combustion systems" (CCV) (Volkswagen, 2003) or "diesotto" cycles (Mercedes-Benz) are based on synthetic fuels (synthetic diesel, biomass to liquid (BTL) or gas to liquid (GTL)).

Manufacturing

The manufacturing of powertrain components and systems is a key factor in the competitive position of companies in the automotive and other (truck, motorcycle, tractor, construction equipment…) vehicle industrial sectors. Global economic and environmental factors have led to the requirement to engineer and produce powertrain system that are more economical to manufacture, higher in product quality and reliability, higher in performance, more fuel efficient, less polluting, and longer in life expectancy. In turn these trends have led to designs that involve higher internal pressures, are subject to greater instantaneous forces, and are more complex in their design and mechanical operation. The resulting advanced powertrain designs in turn impose significantly more severe requirements on the shape, flatness, waviness, roughness, and porosity,of powertrain subsystems, as well as limitations on the allowed presence of potential defects in the surfaces and other dimensional characteristics of the system components and assemblies. In addition to improved materials and material forming methods, these requirements have led to advanced metrology technology that more thoroughly and accurately measures and enables improved control of all of the steps in powertrain manufacturing processes.