A drive wheel is a wheel of a motor vehicle that transmits force, transforming

torque In physics and mechanics, torque is the rotational equivalent of linear force. It is also referred to as the moment of force (also abbreviated to moment). It represents the capability of a force to produce change in the rotational motion of th ...

into

tractive force As used in mechanical engineering, the term tractive force can either refer to the total traction a vehicle exerts on a surface, or the amount of the total traction that is parallel to the direction of motion. In railway engineering, the term tr ...

from the tires to the road, causing the vehicle to move. The

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

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, e ...

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

four-wheel drive Four-wheel drive, also called 4×4 ("four by four") 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 cas ...

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 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 longitu ...

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. Opperman Motor Cart, Bolnhurst - geograph

Opperman Motor Cart, Bolnhurst - geograph

A rare example of front wheel drive was the

Opperman Motocart : ''There are also several persons called Opperman, listed at Opperman (disambiguation)'' S E Opperman was a tractor manufacturer in England. After he saw the Bond Minicar he decided to build his own four-wheel microcar at a factory in Elstree, ...

. 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 and torque and rotation, usually used to connec ...

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-wheel ...

. 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, 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 tires with de ...

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 or 10×10 is a

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

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 and

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

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 sup ...

(PLS), the U.S. Marine's 10x10

Oshkosh Logistic Vehicle System Replacement (LVSR) The Logistic Vehicle System Replacement (LVSR) is a family of heavy-duty military logistics vehicles of the United States Marine Corps (USMC) based on a common 5-axle ten-wheel drive (10x10) chassis. The vehicles vary in individual configuration ...

, 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, often shortened to 12WD or 12×12, refers to a twelve-wheeled

vehicle A vehicle (from la, vehiculum) is a machine that transports people or cargo. Vehicles include wagons, bicycles, motor vehicles (motorcycles, cars, trucks, buses, mobility scooters for disabled people), railed vehicles (trains, trams), ...

with a

that allows all twelve

wheels A wheel is a circular component that is intended to rotate 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 axles, allow heavy objects to b ...

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 ...

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

purposes.