With the rapid advancement in vehicle-to-vehicle (V2V) communications, there are growing interests in related fields to leverage V2V communications for different applications. A robust leader selection algorithm is required in a number of V2V communications related applications. In this paper, a distributed leader selection algorithm is introduced for vehicular ad-hoc network (VANET) over unreliable V2V communications. The algorithm is simple, light-weighted and tightly integrated with SAE 2735 protocol in vehicular networks. The goal of the algorithm is to provide a robust leader selection method for a group of vehicles to determine a temporary leader locally in very short time, which could benefit a lot of newly proposed applications based on V2V in traffic control and autonomous driving related areas. Theoretical analysis as well as simulation results has verified the convergence time, robustness and other aspects of the algorithm.