Differential gear, in automotive mechanics, gear arrangement that permits power from the engine to be transmitted to a pair of driving wheels, dividing the force equally between them but permitting them to follow paths of different lengths, as when turning a corner or traversing an uneven street. On a straight road the tires rotate at the same rate; when turning a part the outside wheel provides farther to move and can turn faster compared to the inner steering wheel if unrestrained.

The components of the Ever-Power differential are proven in the Figure. The energy from the transmitting is delivered to the bevel ring equipment by the drive-shaft pinion, both which are kept in bearings in the rear-axle housing. The case can be an open boxlike structure that is bolted to the ring gear possesses bearings to support a Differential Gear couple of pairs of diametrically opposite differential bevel pinions. Each wheel axle is attached to a differential side equipment, which meshes with the differential pinions. On a directly road the tires and the medial side gears rotate at the same swiftness, there is no relative motion between your differential aspect gears and pinions, and they all rotate as a device with the case and band gear. If the automobile turns left, the right-hand steering wheel will be required to rotate faster than the left-hand steering wheel, and the side gears and the pinions will rotate relative to each other. The ring equipment rotates at a quickness that is add up to the mean acceleration of the still left and right wheels. If the tires are jacked up with the transmitting in neutral and one of the wheels is turned, the opposite wheel will turn in the opposite direction at the same quickness.

The torque (turning minute) transmitted to the two wheels with the Ever-Power differential may be the same. Consequently, if one wheel slips, as in ice or mud, the torque to the other wheel is decreased. This disadvantage can be overcome relatively by the utilization of a limited-slide differential. In one edition a clutch connects among the axles and the band gear. When one wheel encounters low traction, its inclination to spin can be resisted by the clutch, hence providing better torque for the additional wheel.
A differential in its most basic form comprises two halves of an axle with a equipment on each end, linked with each other by a third equipment creating three sides of a square. This is normally supplemented by a 4th gear for added strength, completing the square.