A Locker is a mechanical unit that is sensitive to torque application. It will lock (drive both wheels) under acceleration, or unlock (allow the axles to turn at different rates) during coast or deceleration. A very strong piece, since it doesn’t use any clutches or cones that can wear out, which made it a good choice for it’s original truck application. Since driver input mainly determines whether the unit is locked or not, it can be very frustrating to a driver who is unfamiliar with the operation of the differential. Hard acceleration during a turn will cause the unit to lock and skid the tire. Between lock and unlock, a distinctive “clunk” can be heard. During a properly executed turn, clicking will be audible since locking teeth are allowed to jump each other inside the unit.