CDL Class A Practice Test

The recommended following distance at highway speeds is typically around 3 seconds. This distance allows for a safe reaction time in case the vehicle in front of you suddenly stops or slows down. By maintaining a 3-second gap, drivers can better assess their surroundings and manage their speed in relation to the vehicle ahead. To determine this distance, drivers can use the "three-second rule." They can pick a stationary object on the roadside and begin counting the seconds as the rear of the vehicle in front passes it. If they pass the same object before reaching three seconds, they are following too closely and should increase their distance. A shorter following distance, like 1-second or even 2-seconds, does not provide enough time for the driver to react in most driving scenarios, increasing the risk of collisions. While some might think longer distances, such as 4 seconds, could be advisable in certain conditions, a 3-second following distance is generally considered sufficient for highway speeds under normal circumstances.