8x8x8
Abbreviation of 8 wheel steering with 8 drive wheels on 8 wheels (“an eight-wheeled vehicle with eight-wheel drive and eight-wheeled steering, each wheel has powered drive, and each axle is steerable”).
8x8x8: full-time all-wheel drive and steer on eight axles
An 8x8x8 vehicle is an eight-wheeled truck or platform with eight driven wheels and eight steerable wheels, meaning every wheel receives engine power and every wheel can turn independently. This configuration is almost exclusively found in heavy military vehicles, specialized recovery trucks, and extreme-terrain industrial equipment where traction and directional control matter more than fuel economy or speed. The notation breaks down as: first "8" for total wheels, second "8" for driven wheels, third "8" for steerable wheels.
The steering arrangement typically places the front two axles under direct steering control, with mid and rear axles capable of crab steering (turning at angles to the chassis) or articulated steering to reduce turning radius. Some systems gang the rear axles together mechanically; others use independent hydraulic control. Drive is fed through transfer cases and differentials to each wheel end, often with locking differentials on multiple axles to handle severe obstacles and soft ground without high-centering.
Why this matters in practice
The 8x8x8 layout solves a specific problem: moving massive loads (20 to 40 tonnes or more) across roadless terrain without getting bogged down. A conventional 6x6 with three driven axles concentrates ground pressure; spreading load across eight contact patches dramatically lowers psi and improves traction on sand, mud, and snow. The all-wheel steering allows turning within a footprint only slightly larger than the vehicle's length, critical when navigating narrow mountain passes or tight forest tracks.
Fuel consumption and tire wear are substantial penalties. Keeping eight wheels rolling, steering, and powered requires robust hydraulics, heavier frames, and continuous maintenance of steering linkages and drive shafts. Tire replacements cost thousands per set. These vehicles are bought only when no smaller platform can do the job, or when the mission value justifies extreme operating costs.
Most 8x8x8s you will encounter are military vehicles like the Fuchs Transportpanzer, specialized bridge-layers, or arctic/desert expedition vehicles. Civilian variants appear in remote mining, oil well servicing, and heavy recovery work. The term itself is engineering shorthand, not a formal classification, so variations exist: some 8x8 platforms have only six steerable wheels, for instance.