Merging of entering traffic is one of the primary causes of traffic congestion on freeways. If the movements of the vehicles entering the freeway can be coordinated in advance with the movements of the vehicles already driving along the mainline freeway, the disturbances in vehicle speed at the merge point can be reduced, leading to reductions in congestion and travel delay. These effects are modeled here using a high-fidelity traffic microsimulation model. The effects are simulated for a baseline case with conventional manual merging as well as cases with 50%, 60%, 75% and 100% market penetration of vehicles equipped with V2V coordination and automated merge control capabilities. The effects of V2V communication limitations (delays and packet losses) and vehicle location measurement errors are also assessed.