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 (that is, to receive power from the engine) 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.
When such a vehicle only has eight wheels by definition all are driven. When it has twelve – with two pairs of ganged "dual" wheels on each rear axle – all are also driven but the 8×8 designation remains. Very occasionally, on the Sterling T26 for example, the two front axles can be fitted with ganged "dual" wheels.[1] For most military applications where traction/mobility are considered more important than payload capability, single wheels on each axle (often referred to as super singles) are the norm. On some vehicles, usually recovery trucks or heavy tractor units, the rear two axles will have wider single tires than the front two axles.[2]
Heavy hauler and ballast tractor 8×8s have had a long history as prime movers both in the military (as tank transports and artillery tractors), and commercially in logging and heavy equipment hauling both on- and off-road. Most eight-wheel drive trucks have two forward axles and two at the rear, with only the front pair steering. Occasionally a single front axle and three rear (tridem) are seen, an example being the Oshkosh M1070tank transporter. In such configurations, the front and rear axle usually steer.[3] Other set ups include that of the ZIL-135.
Many wheeled armored vehicles. have an 8x8 driveline, and on these the axles (which usually have independent suspension) are more evenly spaced. Latest generation 8x8 wheeled armored vehicles have steering on the rearmost (fourth) axle to improve mobility in urban and confined situations.[4][unreliable source?]
In the case of both truck and armored vehicle applications, drive may be limited to the rear two axles for on-road use, this reducing driveline stress and tire wear, and increasing fuel efficiency.
Galleryedit
Eliica, the eight-wheeled electric car of Hiroshi Shimizu.
Kynos Aljaba 8x8 tank transporter tractor with wide-footprint tyres
Boxer APC; note the single tyres and near-equal spacing of the front and rear wheel pairs
The Oshkosh M1070 HET is unusual in that while an 8x8 it has a single driven front axle, and a driven rear tridem
This TATRA T 815 recovery truck has dual rear wheels (12 wheels in all) but is still categorized as an 8x8
This 8x8 fire truck is unusual in that it steers by frame articulation
On most wheeled armoured 8x8s the front two axles steer, although on current generation offerings it is becoming more common for the rear axle to contra-steer, this improving maneuverability in confined spaces
It is not unusual for longer wheelbase trucks with four axles to have greater spacing between the front axle pair (the steering axles), as this helps reduce turning circle
The DAF YP 408 APC may appear to be an 8x8 but in fact the second axle is not driven, making the configuration 8x6
"Stryker Armoured Combat Vehicle Family, United States of America". Arms Technology. Retrieved 29 January 2013.
"Piranha III / LAV III Armoured Wheeled Vehicles, Switzerland". Arms Technology. Retrieved 29 January 2013.
Wikimedia Commons has media related to 8×8 vehicles.
April 09, 2024
eight, wheel, drive, often, notated, drivetrain, configuration, that, allows, eight, wheels, eight, wheeled, vehicle, drive, wheels, that, receive, power, from, engine, simultaneously, unlike, four, wheel, drive, drivetrains, configuration, largely, confined, . 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 that is to receive power from the engine 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 Chassis of an 8 8 vehicle Contents 1 Operation 2 Gallery 3 See also 4 References 5 External linksOperation editWhen such a vehicle only has eight wheels by definition all are driven When it has twelve with two pairs of ganged dual wheels on each rear axle all are also driven but the 8 8 designation remains Very occasionally on the Sterling T26 for example the two front axles can be fitted with ganged dual wheels 1 For most military applications where traction mobility are considered more important than payload capability single wheels on each axle often referred to as super singles are the norm On some vehicles usually recovery trucks or heavy tractor units the rear two axles will have wider single tires than the front two axles 2 Heavy hauler and ballast tractor 8 8s have had a long history as prime movers both in the military as tank transports and artillery tractors and commercially in logging and heavy equipment hauling both on and off road Most eight wheel drive trucks have two forward axles and two at the rear with only the front pair steering Occasionally a single front axle and three rear tridem are seen an example being the Oshkosh M1070 tank transporter In such configurations the front and rear axle usually steer 3 Other set ups include that of the ZIL 135 Many wheeled armored vehicles have an 8x8 driveline and on these the axles which usually have independent suspension are more evenly spaced Latest generation 8x8 wheeled armored vehicles have steering on the rearmost fourth axle to improve mobility in urban and confined situations 4 unreliable source In the case of both truck and armored vehicle applications drive may be limited to the rear two axles for on road use this reducing driveline stress and tire wear and increasing fuel efficiency Gallery edit nbsp Eliica the eight wheeled electric car of Hiroshi Shimizu nbsp Kynos Aljaba 8x8 tank transporter tractor with wide footprint tyres nbsp Boxer APC note the single tyres and near equal spacing of the front and rear wheel pairs nbsp The Oshkosh M1070 HET is unusual in that while an 8x8 it has a single driven front axle and a driven rear tridem nbsp This TATRA T 815 recovery truck has dual rear wheels 12 wheels in all but is still categorized as an 8x8 nbsp This 8x8 fire truck is unusual in that it steers by frame articulation nbsp On most wheeled armoured 8x8s the front two axles steer although on current generation offerings it is becoming more common for the rear axle to contra steer this improving maneuverability in confined spaces nbsp It is not unusual for longer wheelbase trucks with four axles to have greater spacing between the front axle pair the steering axles as this helps reduce turning circle nbsp The DAF YP 408 APC may appear to be an 8x8 but in fact the second axle is not driven making the configuration 8x6See also editH drive Six wheel drive Four wheel drive 6x4 drivetrain Driveline windupReferences edit US Army Sterling T26 8 x 8 12 ton Heavy Truck milweb net Retrieved 2016 02 11 Tatra 816 6VWN9T 43 610 8x8 1RTruck Retrieved 2016 02 11 Oshkosh M1070A1 Archived from the original on 2015 10 11 Retrieved 2016 02 11 Piranha 5 army technology com Retrieved 2016 02 11 External links edit Stryker Armoured Combat Vehicle Family United States of America Arms Technology Retrieved 29 January 2013 Piranha III LAV III Armoured Wheeled Vehicles Switzerland Arms Technology Retrieved 29 January 2013 nbsp Wikimedia Commons has media related to 8 8 vehicles Retrieved from https en wikipedia org w index php title Eight wheel drive amp oldid 1162904360, wikipedia, wiki, book, books, library,
