Six-wheel drive, 6WD or 6x6 is a drivetrain

Powertrain

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, drive shafts, differentials, and the final drive...

 configuration of six wheels, all of which are driven simultaneously by the vehicle's engine. Unlike four-wheel drive

Four-wheel drive

Four-wheel drive, 4WD, or 4×4 is a four-wheeled vehicle with a drivetrain that allows all four wheels to receive torque from the engine simultaneously...

 drivetrains, the configuration is largely confined to off-road and military vehicles, particularly heavy-duty ones. Six-wheel drive vehicles may have two wheels at the front and four at the rear (with only the front pair steering), or three evenly spaced axles, where the front and middle pair may both steer (as in the Alvis Saladin

Alvis Saladin

The Saladin is a six-wheeled armoured car built by Alvis, and fitted with a 76mm gun.Used extensively by the British Army, it replaced the AEC Armoured Car that had been in service since World War II.-History:...

). Drive may be limited to the rear two axles for on-road use.

T815

Tatra T815

Tatra T815 is a truck family, produced by Czech company Tatra. It uses the traditional tatra concept of rigid backbone tube and swinging half-axles giving independent suspension. The vehicles are available in 4x4, 6x6, 8x8, 10x8, 10x10, 12x8 and 12x12 variants. There are both air-cooled and...

, M35 2-1/2 ton cargo truck

M35 2-1/2 ton cargo truck

The M35 family of trucks is a long-lived vehicle initially deployed by the United States Army, and subsequently utilized by many nations around the world. A truck in the 2½ ton weight class, it was one of many vehicles in U.S...

 (aka "Deuce and a half") and the Pinzgauer High Mobility All-Terrain Vehicle

Pinzgauer High Mobility All-Terrain Vehicle

The Pinzgauer is a family of high-mobility all-terrain 4WD and 6WD military utility vehicles. They were manufactured in Guildford, Surrey, United Kingdom, by BAE Systems Land & Armaments. The vehicle was originally developed in the late 1960s by Steyr-Daimler-Puch of Graz, Austria, and was named...

 are production examples of vehicles using this type of drive system.

The Alvis Stalwart is an amphibious 6x6 military truck built by Alvis that served with the British Army.

Six-wheeled conversions of four-wheel drive trucks are widely made. These may be six-wheel drive (such as the 6x6 version of the Australian Army

Australian Army

The Australian Army is Australia's military land force. It is part of the Australian Defence Force along with the Royal Australian Navy and the Royal Australian Air Force. While the Chief of Defence commands the Australian Defence Force , the Army is commanded by the Chief of Army...

's Perentie

Land Rover Perentie

The Land Rover Perentie is a vehicle in use by the Australian Army, produced in Australia and based on the Land Rover Defender 110. It was introduced in 1987 to replace the ageing fleet of Series 2A and 3 Land Rovers, and is still in service...

 Land Rover Defender and the 6x6 Australia company's "Landcruiser Sherman"), but are commonly 6x4 (with only front and rear or front and middle axles driven), a technically simpler construction with stock components. Polaris Industries

Polaris Industries

Polaris Industries is a manufacturer of snowmobiles, ATV, and neighborhood electric vehicles. Polaris is based in Medina, Minnesota, USA. The company also manufactures motorcycles through its Victory Motorcycles subsidiary and through the Indian Motorcycle subsidiary which it purchased in April...

 has produced a number of 6 wheel drive ATVs and UTVs for many years now, they are based on a standard Magnum, Sportsman or Ranger with an extra axle and a Cargo Box over the rear wheels. John Deere also produced a 6 wheel Gator

John Deere Gator

The John Deere Gator is a family of small all-terrain utility vehicles produced by the John Deere Corporation. They typically feature a box bed, similar in function to a pickup truck, and have been made in a variety of configurations, ranging from 4 to 6 wheels. The Gator line of vehicles are...

 model, but only the rear wheels have power. There are also a number of companies who produce 6x6 and 8x8 amphibious ATVs