Abstract: An apparatus for sensing the angular velocity of a vehicle wheel includes a sleeve, a tone wheel detachably coupled to the sleeve, and an electromagnetic sensor. The sleeve can be rotatably mounted on bushings inside a differential housing. The electromagnetic sensor extends through a wall of the housing into close proximity to a periphery of the tone wheel which has a plurality of generally radially extending evenly spaced teeth formed thereon. The tone wheel is positioned on the sleeve between a pair of retaining rings and is keyed for rotational movement with the sleeve. An inner end of the sleeve has means for coupling to the side gear of a differential carrier assembly. In one embodiment, the means for coupling includes tabs formed on the sleeve and cooperating slots formed on a side gear. In another embodiment, lugs formed on the sleeve engage driving surfaces formed on the side gear.