Drive wheel

Front-wheel drive (FWD) is a form of engine and transmission layout used in motor vehicles, where the engine drives the front wheels only. Most modern front-wheel drive vehicles feature a transverse engine, rather than the conventional longitudinal engine arrangement generally found in rear-wheel drive and four-wheel drive vehicles.

A monowheel tractor or monowheel-drive tractor is a light transport and agricultural vehicle that is driven and controlled by an engine and steering mechanism mounted on a single large wheel, with the load-carrying body trailing behind. Despite the name, they are tricycles.

A drive shaft, driveshaft, driving shaft, tailshaft, propeller shaft, or Cardan shaft is a component for transmitting mechanical power and torque and rotation, usually used to connect other components of a drivetrain that cannot be connected directly because of distance or the need to allow for relative movement between them.

A differential is a gear train with three drive shafts that has the property that the rotational speed of one shaft is the average of the speeds of the others. A common use of differentials is in motor vehicles, to allow the wheels at each end of a drive axle to rotate at different speeds while cornering. Other uses include clocks and analog computers.

An all-wheel drive vehicle is one with a powertrain capable of providing power to all its wheels, whether full-time or on-demand.

Four-wheel drive, also called 4×4 or 4WD, refers to a two-axled vehicle drivetrain capable of providing torque to all of its wheels simultaneously. It may be full-time or on-demand, and is typically linked via a transfer case providing an additional output drive shaft and, in many instances, additional gear ranges.

Rallying is a wide-ranging form of motorsport with various competitive motoring elements such as speed tests, navigation tests, or the ability to reach waypoints or a destination at a prescribed time or average speed. Rallies may be short in the form of trials at a single venue, or several thousand miles long in an extreme endurance rally.

An off-road vehicle, sometimes referred to as an overland or adventure vehicle, is considered to be any type of vehicle which is capable of driving on and off paved or gravel surface. It is generally characterized by having large tyres with deep, open treads, a flexible suspension, or even caterpillar tracks. Other vehicles that do not travel on public streets or highways are generally termed off-highway vehicles, including tractors, forklifts, cranes, backhoes, bulldozers, and golf carts.

Six-wheel drive is an all-wheel drive drivetrain configuration of three axles with at least two wheels on each axle capable of being driven simultaneously by the vehicle's engine. Unlike four-wheel drive drivetrains, the configuration is largely confined to heavy-duty off-road and military vehicles, such as all-terrain vehicles, armored vehicles, and prime movers.

Eight-wheel drive, often notated as 8WD or 8×8, is a drivetrain configuration that allows all eight wheels of an eight-wheeled vehicle to be drive wheels simultaneously. Unlike four-wheel drive drivetrains, the configuration is largely confined to heavy-duty off-road and military vehicles, such as armored vehicles, tractor units or all-terrain vehicles such as the Argo Avenger.

The Palletized Load System (PLS) is a truck-based logistics system that entered service in the United States Army in 1993. It performs long and short distance freight transport, unit resupply, and other missions in the tactical environment to support modernized and highly mobile combat units. It provides rapid movement of combat configured loads of ammunition and all classes of supply, shelters and intermodal containers. It is similar to systems such as the British Demountable Rack Offload and Pickup System (DROPS).