A differential for use in a vehicle drive train having a pair of rotary members including a gear case that is operatively supported in driven relationship with respect to the drive train and a pair of side gears mounted for rotation with a respective one of the rotary members in the gear case. The differential also includes a spider mounted for rotation with the gear case and at least one pair of pinion gears mounted for rotation with the spider and in meshing relationship with the side gears. The side gears have concave teeth flanks and the pinion gears have convex teeth flanks to increase power density through the differential.