Abstract: A differential gear device including: a differential casing; and a pair of side gears which are disposed within the differential casing such that the side gears are rotatable about the above-indicated axis and are axially opposed to each other, and such that a rotary motion of the differential casing about the above-indicated axis is transmitted to the side gears through at least one pinion gear, the differential casing having a pair of bearing portions which extend from its respective inner surfaces toward back surfaces of the respective side gears, which are coaxial with said axis and which have respective annular seating surfaces which receive axial loads from the side gears, and wherein each of the pair of bearing portions has a protrusion extending from an outer circumference of corresponding one of the annular seating surfaces in a radially outward direction of the annular seating surface.

Abstract: A differential gear device including: a differential casing; and a pair of side gears which are disposed within the differential casing such that the side gears are rotatable about the above-indicated axis and are axially opposed to each other, and such that a rotary motion of the differential casing about the above-indicated axis is transmitted to the side gears through at least one pinion gear, the differential casing having a pair of bearing portions which extend from its respective inner surfaces toward back surfaces of the respective side gears, which are coaxial with said axis and which have respective annular seating surfaces which receive axial loads from the side gears, and wherein each of the pair of bearing portions has a protrusion extending from an outer circumference of corresponding one of the annular seating surfaces in a radially outward direction of the annular seating surface.