Patent ID: 8419583

Claim:
A front differential for a four wheel drive vehicle, comprising: a differential case having a tapered inner wall contact surface; a switching mechanism that switches the vehicle between rear-wheel drive and front- and rear-wheel drive by selectively interrupting or allowing the transmission of power between one of a pair of side gears and one of a pair of front wheels, each one of the pair of side gears having a tapered contact surface; and an urging mechanism disposed within the differential case, the urging mechanism urges at least one of the pair of side gears in a drive shaft axial direction toward at least one of the front wheels; wherein the urging mechanism urges at least one of the tapered contact surfaces of the pair of side gears against the tapered inner wall contact surface of the differential case, the tapered contact surfaces of the pair of side gears and the tapered inner wall contact surface of the differential case are processed to reduce friction.