In this research, we propose a novel vehicle-to-vehicle (V2V) visible light communications (VLC)-based system model under shadowing. Shadowing significantly affects the path loss, which arises due to the blockage of the line-of-sight path, on the VLC link performance. Moreover, we analyze the performance of the considered system using the diversity-multiplexing tradeoff (DMT) metric. Note that DMT provides an optimal tradeoff between the diversity gain and the multiplexing gain. Further, DMT provides the operating points which play a significant role in the design of the communication system. In this research, we first model the V2V-VLC system based on the probabilistic behavior of the shadowing, followed by analyzing the corresponding DMT. In addition, we investigate the optimal DMT for a practical transmission scenario, where there is a possibility that the VLC link may experience an outage. Furthermore, we investigate the system performance under the atmospheric turbulence conditions. Finally, the entire study and the subsequent analysis is acknowledged by means of useful remarks and interesting observations that have not been previously identified in the literature.