Many such vehicles have a locking differential on the central differential (between the front and rear axles), rear differential and front differential, or any combination of any of the three. Differential locks are also used on some "non-utility" four-wheel-drive vehicles (such as the Mitsubishi Shogun) to compensate for a relative lack of axle articulation (vertical wheel movement). High amounts of articulation are desirable for off-road driving, to allow the wheels to maintain ground contact over uneven surfaces, but this can lead to excessive body-roll at high speeds on the road, as well as vague steering. Such 4x4s often have suspension systems designed as a compromise between articulation and handling. If articulation is limited, one wheel on an axle may be lifted off the ground by rough terrain, thus losing all traction to all wheels (all power goes to the lifted wheel, which spins freely). A rear locking differential is often supplied to make up for this compromiseif a wheel is lifted off the ground, the locking differential can be activated, driving the wheel that remains on the ground. References Automotive transmission technologies