We propose and analyze an information-sharing application for wireless intervehicular networks, called Infoshare. Infoshare leverages the broadcast nature of the wireless medium to achieve maximum spreading of information queries among vehicles, while a smart caching policy limits the overhead resulting from useless queries and duplicated replies. We first evaluate the performance of Infoshare through the simulator ns2, highlighting the impact of various system parameters on the information spreading dynamics. Then, we develop an analytical model of the information exchange dynamics, which allows us to identify the system parameters that guarantee a sustainable information exchange on the network scenario under study. c 2006 Elsevier B.V. All rights reserved.