A differential is a device with gears that is connected by three shafts, and transmits torque and rotation. In cars and trucks, a differential lets the wheels rotate at different speeds. This helps to stabilize the vehicle as the wheel that is on the outside of the curve turn faster and roll farther. An increase in the speed of one wheel must be balanced by an equal decrease in the speed of the other. Because of dynamics, an increase in the speed of one wheel must be balanced by an equal decrease in the speed of the other wheel.
In vehicles without a differential, both driving wheels must rotate at the same speed, usually on a common axle. When cornering, the inner wheel needs to travel a shorter distance than the outer wheel, so without a differential, the inner wheel spins and/or the outer wheel drags, and this results in unpredictable handling, tire damage, and ultimately possible failure of the drive train.
Can All Mechanics Do Differential Repair?
Not all them, no. Some mechanics don’t know how to do differential repair, and they contract it out to shops that rebuild in house like Barrett Transmission.