A drive wheel is a

wheel A wheel is a rotating component (typically circular in shape) that is intended to turn on an axle Bearing (mechanical), bearing. The wheel is one of the key components of the wheel and axle which is one of the Simple machine, six simple machin ...

of a

motor vehicle A motor vehicle, also known as a motorized vehicle, automotive vehicle, automobile, or road vehicle, is a self-propelled land vehicle, commonly wheeled, that does not operate on railway track, rails (such as trains or trams), does not fly (such ...

that transmits force, transforming

torque In physics and mechanics, torque is the rotational analogue of linear force. It is also referred to as the moment of force (also abbreviated to moment). The symbol for torque is typically \boldsymbol\tau, the lowercase Greek letter ''tau''. Wh ...

into tractive force from the tires to the road, causing the vehicle to move. The

powertrain In a motor vehicle, the powertrain comprises the main components that generate engine power, power and deliver that power to the road surface, water, or air. This includes the internal combustion engine, engine, transmission (mechanics), trans ...

delivers enough torque to the wheel to overcome stationary forces, resulting in the vehicle moving forwards or backwards. A

two-wheel drive Two-wheel-drive (2WD) denotes vehicles with a drivetrain that allows two wheels to be driven, and receive power and torque from the engine, simultaneously. Four-wheeled vehicles For four-wheeled vehicles (and by extension, vehicles with six, ...

vehicle has two driven wheels, typically both at the front or back, while a

four-wheel drive A four-wheel drive, also called 4×4 ("four by four") or 4WD, is 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 pr ...

has four. A steering wheel is a wheel that turns to change the direction of a vehicle. A trailer wheel is one that is neither a drive wheel, nor a steer wheel.

Front-wheel drive Front-wheel drive (FWD) is a form of internal combustion engine, engine and transmission (mechanics), transmission layout used in motor vehicles, in which the engine drives the front wheels only. Most modern front-wheel-drive vehicles feature ...

vehicles typically have the rear wheels as trailer wheels.

Drive wheel configurations

Front-wheel drive

Front-wheel drive (FWD) vehicles' engines drive the front wheels. Using the front wheels for delivery of power as well as steering allows the driving force to act in the same direction as the wheel is pointing. This layout is commonly used in modern passenger cars. A rare example of front wheel drive was the Opperman Motocart. This slow-speed agricultural and light freight vehicle was a tricycle with the front wheel carrying a large tractor tyre. The wheel was powered by a small single cylinder Douglas engine carried on the front mono fork that formed the steering gear. See also

Front-engine, front-wheel drive layout In automotive design, a front-engine, front-wheel-drive (FWD) layout, or FF layout, places both the internal combustion engine and driven roadwheels at the front of the vehicle. Usage implications Historically, this designation was used reg ...

Rear-wheel drive

Rear-wheel drive (RWD) typically places the engine in the front of the vehicle, with a

driveshaft A drive shaft, driveshaft, driving shaft, tailshaft (Australian English), propeller shaft (prop shaft), or Cardan shaft (after Girolamo Cardano) is a component for transmitting mechanical power, torque, and rotation, usually used to connect ...

running the length of the vehicle to the differential transmission. However, mid engine and rear engine layouts can also be used. It was a common layout used in automobiles throughout the 20th century. At this time, FWD designs were not practical due to complexity (in FWD, engine power and steering must both be combined in the front axle).

Two-wheel drive

For four-wheeled vehicles, two-wheel drive describes vehicles that transmit torque to at most two road wheels, referred to as either front- or

rear-wheel drive Rear-wheel drive (RWD) is a form of engine and transmission layout used in motor vehicles, in which the engine drives the rear wheels only. Until the late 20th century, rear-wheel drive was the most common configuration for cars. Most rear-whee ...

. The term 4x2 is also used, to indicate four total road-wheels with two being driven. For vehicles that have partial four-wheel drive, the term two-wheel drive refers to the mode when four-wheel drive is deactivated and torque is applied to only two wheels.

All-wheel drive

Four-wheel drive

This configuration allows all four road wheels to receive torque from the power plant simultaneously. It is often used in rally racing on mostly paved roads. Four-wheel drive is common in

off-road vehicle An off-road vehicle (ORV), also known as an off-highway vehicle (OHV), overland vehicle or adventure vehicle, is a type of transportation specifically engineered to navigate unpaved roads and surfaces. These include trails, forest roads, and ...

s because powering all four wheels provides better control on loose and slippery surfaces. Four-wheel drive manufacturers have different systems such as "High Range 4WD" and "Low Range 4WD". These systems may provide added features such as a varying of torque distribution between axles or varying gear ratios. Common terms for this configuration include four-wheel drive, 4WD, 4x4 (pronounced "four-by-four"), integral, and all-wheel drive (AWD).

Six-wheel drive

Eight-wheel drive

Ten-wheel drive

Ten-wheel drive (10WD, 10×10) is a

drivetrain A drivetrain (also frequently spelled as drive train or sometimes drive-train) or transmission system, is the group of components that deliver mechanical power from the prime mover to the driven components. In automotive engineering, the driv ...

configuration of ten wheels, all of which are driven simultaneously by the engine. Unlike four-wheel drive drivetrains, this configuration is only used in extreme

off-road Off-roading is the act of driving or riding in a vehicle on unpaved surfaces such as sand, dirt, gravel, riverbeds, mud, snow, rocks, or other natural terrain. Off-roading ranges from casual drives with regular vehicles to competitive events w ...

and

military A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. Militaries are typically authorized and maintained by a sovereign state, with their members identifiable by a d ...

uses, in particular heavy haulage and missile carriers. Some severe/extreme duty semi tractors may also have this drive configuration. The Oshkosh M1074 and M1075 prime mover units in the U.S. Army's

Palletized Load System 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 s ...

(PLS), the U.S. Marine's 10x10 Oshkosh Logistic Vehicle System Replacement (LVSR), and the Tatra T816 10×10 cargo carrier are examples of ten-wheel drive vehicles. 10x10's are not as common as 4×4's, 6×6's and 8×8's.

Twelve-wheel drive

Twelve-wheel drive (12WD, 12×12), refers to a twelve-wheeled

vehicle A vehicle () is a machine designed for self-propulsion, usually to transport people, cargo, or both. The term "vehicle" typically refers to land vehicles such as human-powered land vehicle, human-powered vehicles (e.g. bicycles, tricycles, velo ...

with a

that allows all twelve

wheels A wheel is a rotating component (typically circular in shape) that is intended to turn on an axle bearing. The wheel is one of the key components of the wheel and axle which is one of the six simple machines. Wheels, in conjunction with axl ...

to receive power from the

engine An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ge ...

simultaneously. This configuration is typically used in heavy-duty and extreme

and

purposes.