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Dual Clutch Transmissions have conquered an important fraction of the market, mainly in Europe, as a result of their improvements concerning efficiency. Once the power flow from engine to the transmission is not interrupted, fuel efficiency increases radically. Furthermore, extreme fast and soft shifts provide the most dynamic and smooth acceleration of any vehicle on the market, being particularly suitable on high performance vehicles. The drivers have also experienced singular comfort, since they can choose whether to control the shifting or let the computer do it automatically. Nevertheless, to overcome the elevated requirements imposed to the system components, in special the release bearings, the industry has dispended considerable efforts on the development of new processes and design methodologies.

The design of Clutch Release Bearings (CRB) is usually based on angular contact ball bearings. This kind of bearings supports both axial and radial loads and the load limits depend directly on the contact angle. The CRB has its own particularity, since it is a radial angular contact ball bearing and its main load is on axial direction. Due to this special situation, this work is done to evaluate this CRB design according to the classical theory of bearing life calculation, developed by Lundberg and Palmgren (1947), which the standard ISO 281 is based on. The analysis is focused on the basic dynamic load rating of the bearing, which briefly means the expected load that the bearings support a life of 1 million cycles. This expectation follows a Weibull distribution with increasing failure ratio and a specific reliability.