Differential gear, in automotive mechanics, gear arrangement that allows power from the engine to be transmitted to a pair of generating 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 wheels rotate at the same swiftness; when turning a part the outside wheel offers farther to go and will turn faster than the inner wheel if unrestrained.

The components of the Ever-Power differential are proven in the coupling China Figure. The power from the transmitting is sent 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 one or two pairs of diametrically opposite differential bevel pinions. Each steering wheel axle is attached to a differential side gear, 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 the differential part gears and pinions, and they all rotate as a device with the case and ring gear. If the automobile turns left, the right-hand wheel will be required to rotate faster compared to the left-hand steering wheel, and the side gears and the pinions will rotate relative to each other. The ring gear rotates at a rate that is add up to the mean rate of the still left and right wheels. If the wheels are jacked up with the tranny in neutral and one of the tires is turned, the opposite wheel will submit the opposite direction at the same acceleration.

The torque (turning moment) transmitted to the two wheels with the Ever-Power differential is the same. Therefore, if one steering wheel slips, as in ice or mud, the torque to the other steering wheel is decreased. This disadvantage could be overcome somewhat by the utilization of a limited-slide differential. In one version a clutch connects among the axles and the band gear. When one steering wheel encounters low traction, its inclination to spin can be resisted by the clutch, therefore providing greater torque for the additional wheel.
A differential in its most basic form comprises two halves of an axle with a gear on each end, linked collectively by a third equipment creating three sides of a sq .. This is normally supplemented by a fourth gear for added power, completing the square.