A vehicle wheel bearing apparatus for supporting a driven wheel of a
vehicle has an outer member formed with double row outer raceway surfaces
on its inner peripheral surface. An inner member includes a wheel hub
with an integrally formed wheel mounting flange at one end of the inner
member. A cylindrical portion axially extends from the wheel mounting
flange. At least one inner ring, formed with at least one of double row
inner raceway surfaces, opposes the double row outer raceway surfaces.
The inner ring is adapted to be press-fit onto the cylindrical portion of
the wheel hub. Double row rolling elements are freely rollably contained
between the outer and inner raceway surfaces, respectively, of the outer
and inner members. The inner ring is axially immovably secured relative
to the wheel hub by a caulked portion. The caulked portion is formed by
plastically deforming the end of the axially extending cylindrical
portion radially outward. A partition wall is formed in the axially
extending cylindrical portion of the wheel hub at a portion subjected to
a load applied to at least the inner raceway surface of an inboard side
of the double row inner raceway surfaces. A hollow portion is formed
within the cylindrical portion at a portion outboard from the partition
wall.