What is the safe following distance for highway driving?

The safe following distance for highway driving is at least four seconds behind the vehicle in front of you. This distance provides a sufficient buffer to allow the driver to react to sudden stops or emergencies. At higher speeds typically found on highways, such as 55 mph or more, stopping distances increase significantly, making it crucial to maintain a longer following distance.

Using the four-second rule helps account for factors like road conditions, weather, and vehicle performance. By counting four seconds from when the rear of the vehicle in front passes a fixed point until your vehicle reaches the same point, you can ensure that you have adequate time to respond safely in case of unexpected changes in traffic conditions. This practice also supports general defensive driving principles, which emphasize being prepared for the actions of other drivers and maintaining an escape route if necessary.