Specification and Seal Development for Passenger Vehicle Wheel Bearings

Automotive wheel bearings are sealed and greased for life components. The component life is governed by its resistance to rolling contact fatigue, lubrication and seal performance. A survey of “garage returned” wheel bearings indicated seal failures as a dominating bearing failure mode. Since seal performance is critical to the life of a wheel bearing, a test specification was developed to evaluate the various aspects of seal performance. An application oriented test method was also developed which reproduces the service failure mode. Wheel bearings were tested with relevant suspension components such that influence of the secondary protection systems could also be evaluated in a complete system performance test. The potential of the wheel bearing seal test package is indicated by the description of test and service results of two wheel bearing seal types.