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The ever tightening of fuel economy and greenhouse gas emissions standards globally continues to challenge bearing companies toward lower torque, lower mass products. This paper focuses on improving fuel efficiency by considering the torque of automotive wheel bearing seals. This study establishes the level of drag torque reduction achieved through the structural design of the bearing seals. Wheel bearing seals are a critical component that must pass stringent torque, water exclusion, and other critical OEM and supplier performance specifications. They are designed as non-serviceable and must maintain full performance through the life of the vehicle. As a result of the application of specialized structural design, the drag torque, per the study, is reduced by more than 50% compared to existing bearing specifications. Electric vehicle companies are also seeking low friction wheel bearing solutions to further reduce CO2 (indirect or wheel-to-wheel) emissions.

Automotive wheel bearings have the primary function of translating the rotating motion of the wheels into linear vehicle motion while supporting the vehicle weight. As vehicle lives continue to increase, there is a need for longer service lives than those of existing products. There is an even greater need for performance-related reliability during usage. Lateral stiffness, one of the main parameters of wheel bearing design, has a significant influence on ride comfort and steering feel. In this study, reliability-based weight optimization considering geometric uncertainty for automotive wheel bearings was investigated. Deterministic design optimization (DDO) and reliability-based design optimization (RBDO) were performed. For optimization, the following three key relationships were chosen: wheel bearing specification and geometry for design variables, weight for cost function, and stiffness for constraint.