<div class="htmlview paragraph">One thing that is very important in a carmaker company is its know-how built during all its life. Such an experience allows, for instance, to correlate the customer expected product life with accelerated tests procedures.</div> <div class="htmlview paragraph">When it comes to cars, it is usual to have correlated proving routes in such way that if a prototype can take a number of passing in the proving ground without failure, it is unlikely the car is going to fail during a regular life. In the other hand, if a failure at determined percentage of the test happens, it is predictable that the same failure shows up at the same percentage of the product design life.</div> <div class="htmlview paragraph">This paper proposes a methodology based on the SxN fatigue theory to solve durability issues observed in correlated durability tests.</div>