The evolution of mechanical properties of NR with carbon black fillers was examined after a thermal aging step through both experimentation and non-deterministic numerical simulations. A quantification of mechanical properties and associated variability is first proposed for a set of specimens exposed at different temperatures and exposure times. Second, a family of stretch–stress laws is numerically built with a James' hyperelastic model. Next, the whole of the behavior evolution is modeled with a Kriging model to quantify the effects of properties on a macroscopic stiffness, useful in dynamic simulations, and the least-favorable scenario is so determined. Finally, Arrhenius method is performed to numerically draw the evolution bounds of macroscopic stiffness as a function of aging exposure, followed by a comparison with a naturally aged suspension component. To our knowledge, the methodology developed has not already been proposed in this area.