Torsional Failure
WARNING: This page is about a different car, the 2005 Ford Pickup, 2005 Ford F550 Super Duty, 2005 Ford F450 Super Duty, and 2005 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
If a torsional failure (twisting fracture) of the hublock is suspected or the internal gears are "shattered", the axle constant shaft may have been damaged as well. Inspect the axle shaft carefully; if twisting has occurred at the base of the axle splines, it is difficult to see without removing the bearing assembly.