The self-locking differential controls the torque transmitted to each rear wheel.
Depending on the grip conditions on the road surface, and at low speeds (under 20 mph/30 kph), this device enables wheel torque to move automatically, thereby providing increased grip. This enables the grip potential of each wheel to be used to the fullest possible extent, thereby enabling the vehicle to run over areas with decreased grip (e.g.: work sites, muddy ground, etc.).