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Differential delivers driving force to the wheels while the wheels spin at different speeds due to road conditions. It makes the wheels attached to the suspension act independently.

  • The differential is a device or gear assembly between two shafts that permits the shafts to turn at different speeds if necessary while continuing to transmit torque. It is used in drive axles to allow different rates of wheel rotation on curves. Differentials are used in the rear-drive axle of front-engine rear-wheel-drive vehicles. The transaxles of front-engine, front-wheel drive and rear-engine, rear-wheel-drive vehicles; The front drive axle and rear drive axle of four-wheel-drive vehicles, and the transfer case of some four-wheel-drive vehicles.
  • The differential permits power flow to both drive wheels while allowing the wheels to travel different distances during the turn.
  • Suppose both rear wheels are attached to the ends of a solid shaft, Both wheels would rotate together at the same speed and try to travel the same distance all the time If the vehicle turned each tire would skid an average of 4 ft during a turn. The tires would wear quickly and the vehicle would be difficult to control. The differential avoids these problems, It allows the outer wheel to turn faster and therefore travel farther than the inner wheel during a turn.