In this paper, the authors analyze the performance of cooperative content caching in Vehicular Ad hoc NETworks (VANETs). In particular, they characterize, using analysis and simulations, the behavior of the probability of outage (i.e., not finding a requested data chunk at a neighbor) under freeway vehicular mobility. First, they introduce a formal definition for the probability of outage in the context of cooperative content caching. Second, they characterize, analytically, the outage probability under vehicular and random mobility scenarios. Next, they verify the analytical results using simulations and compare the performance under a number of plausible mobility scenarios.