which forms a small air gap between itself and housing 54 and rotates with carrier assembly 22 the application of electrical energy to solenoid coil 52 causes armature 56 to be attracted toward annular housing 54 tab 73 protrudes from housing 54 and fits into a pocket formed by differential case 18 to position the housing and prevent rotational movement of the housing armature 56 is coupled with a plurality of stanchions or studs 57 which extend axially away from the armature through suitable axial passageways studs 57 are connected with apply plate 58 a pilot or primary friction clutch pack 60 is disposed between an internal surface of end cap 50 and apply plate 58 energization of the solenoid coil 52 urges the armature 56 toward housing 54 which closes the air gap between these components and urges primary clutch apply plate 58 to compress the pilot or primary friction clutch pack 60 primary clutch pack 60 includes a first plurality of larger diameter clutch discs or plates 62 with a male or exterior splines which engage complimentary female splines formed by the inner surface of end cap 50 the clutch plates 62 thus rotate with carrier housing 24 interleaved within the clutch plates 62 is a second plurality of smaller diameter friction clutch discs or plates 64 which engage with complimentary splines of a circular clutch hub 66 both the first and second.