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Rubber compound aging is unavoidable. It changes material molecular structure and mechanical properties resulting in undesirable changes in tire performance. The behavior of aged tires was simulated using the finite element method after investigations regarding the boundary conditions, such as temperature, air composition and time of exposure, to reproduce in laboratory the aging observed in the market. During service life, the tire undergoes repeated and complex stress cycles resulting in heat generation by hysteresis. It is critical in regions like belt edges where temperature measurements show values up to 70°C for passenger car tires and more than 100°C for trucks. The inflated air permeates through the tire components leading to oxidative conditions propitious to fatigue and crack propagation. Aging is related to the tire operational conditions but engineers usually accelerate the process in lab tests by increasing the temperature, following the Arrhenius law.