In this paper we present a sensor inter-vehicle communication protocol based on geographical routing. Sensors installed in cars continuously gather important information about: air bags, distance detection, mechanical and electronic parts, tire pressure, collision force, direction of impact and the car and its passengers? conditions. Our proposed protocol enables transmission of these information on point-to-point communications between cars in highway. The protocol is designed for highway travelers but can be used in any mobile ad-hoc network. The highway is divided in virtual cells, which moves as the vehicles moves. The cell members choose a center that will behave for a certain time interval as a Base Station. Every node has its geographical position given by Global Positioning System (GPS). When a source node has a message for a destination node, forwards it to its Cell Center. Then the message is forwarded through the other Cell Centers. The Cell Centers first verifies if the destination node belongs to their cell. Finally the destination Cell Center will send the message to the destination node. Our simulation results show that our proposed protocol improves the network utilization compared to existing inter-vehicles protocols. The protocol can be used to implement differentiated mobile services and message prioritization. Through simulation evaluations, we show that our protocol is very scalable and reduces the latency compared existing solutions.