Efficiently propagating adequate and effective traffic information to drivers helps increase driving safety and reduces traffic jams on highways. To achieve this, we designed an overlay solution that considers the challenges of propagating multisource information caused by vehicle mobility and multihop forwarding. The overlay solution is composed of a mobility-adaptive information reduction scheme (IR scheme) and a vehicle-adaptive cluster-to-cluster multihop forwarding method (VAC method). The IR scheme creates a mobility-adaptive cluster to represent local traffic information. The purpose of the scheme is to simplify individual high-speed movements and reduce large amounts of information broadcasts. Based on the results of the IR scheme, the VAC method selects the optimal relay node of the intercluster forwarding pair to increase the efficiency of multihop propagation. In the simulation, we compared network performance with two other protocols by defining three objective metrics of driving-perceived quality under different traffic scenarios and analyzed the results. Furthermore, we explored protocol overhead, broadcasting reduction ratio, and technological deviations to verify the advantages and efficiencies of our solution. The simulation proves that our solution is an efficient multisource and multihop forwarding framework that allows well-connected vehicular networks to disseminate a higher degree of correct traffic information, particularly for highway safety-related information.