Following distance and large trucks

Key points

1. Use the four second rule: if you pass the point before counting four, you are too close.

   Source: Handbook p. 27

   “If you pass the same point before you are finished counting, you are following too closely.”
   Alaska Driver Manual, Handbook p. 27

2. When towing or on a wet or slippery road, increase to six seconds or more.

   Source: Handbook p. 27

   “When towing a trailer or the road surface is wet or slippery, increase the four seconds to six or more.”
   Alaska Driver Manual, Handbook p. 27

3. Alaska regulation requires at least the two second rule.

   Source: Handbook p. 27

   “13 AAC 02.090 requires at a minimum the 2 second rule.”
   Alaska Driver Manual, Handbook p. 27

4. On a two lane road outside urban areas, pull over safely when 5 or more vehicles are behind you.

   Source: Handbook p. 27

   “AS 28.35.140 requires drivers on a two-lane roadway outside of an urban area to safely pull over when there are five or more vehicles immediately behind.”
   Alaska Driver Manual, Handbook p. 27

5. Keep brake lights clean and flash them when preparing to stop.

   Source: Handbook p. 27

   “Be sure brake lights are clean and working properly. Flash brake lights when preparing to stop.”
   Alaska Driver Manual, Handbook p. 27

6. In car and truck crashes, car occupants suffer 78% of the fatalities.

   Source: Handbook p. 70

   “In large truck crashes, the occupants of a car, usually the driver, sustain 78% of fatalities.”
   Alaska Driver Manual, Handbook p. 70

7. A car at 55 mph stops in about 130 to 140 feet; a truck needs 400 feet.

   Source: Handbook p. 70

   “A car traveling at 55 mph can stop in about 130 to 140 feet, however a truck needs 400 feet to stop.”
   Alaska Driver Manual, Handbook p. 70

8. If you cannot see the truck driver in the side mirrors, the driver cannot see you.

   Source: Handbook p. 70

   “Remember, if you can't see the truck or bus driver in their side mirrors, they can't see you.”
   Alaska Driver Manual, Handbook p. 70

9. Before pulling in front of a truck you passed, see its whole front in your mirror, then do not slow down.

   Source: Handbook p. 71

   “When passing, look for the whole front of the truck in your rear-view mirror before pulling in front of the truck, and then don’t slow down!”
   Alaska Driver Manual, Handbook p. 71

Numbers to know

3 questions from the Alaska practice test

1. 1. What following interval does the Alaska manual recommend for calculating a safe following distance?

   1. A one-second interval regardless of weather
   2. A one-car-length rule at every speed
   3. The four-second interval method
   4. A ten-second stop at every landmark
   Show answer

   The four-second interval method. The manual describes the four-second interval method: watch the vehicle ahead pass a definite point, then count four seconds and compare your arrival at that point. If you reach it before finishing, the gap is too short. The fixed one-car-length choice fails because distance needed changes with speed, and the one-second choice leaves little reaction time. Towing a trailer or driving on a wet or slippery surface calls for six seconds or more. Pick a roadside object as your reference and count consistently while conditions change.

2. 2. What following interval does Alaska recommend when towing a trailer or driving on a wet or slippery road?

   1. One second, because the trailer slows the vehicle
   2. Six seconds or more
   3. Two seconds in every condition
   4. Four seconds only when traffic is stopped
   Show answer

   Six seconds or more. The four-second method becomes six seconds or more when a driver is towing a trailer or the road surface is wet or slippery. Those conditions increase the time and distance needed to respond, so retaining the ordinary four-second gap is not enough for the recommendation. The two-second figure is a regulatory minimum noted elsewhere, not this expanded safety interval. Choose a fixed point, count the interval after the vehicle ahead passes it, and add space whenever traction or vehicle length raises the stopping demand.

3. 3. In crashes between cars and large trucks, who sustains most of the fatalities, according to the Alaska manual?

   1. Truck drivers in most cases
   2. Pedestrians
   3. Both equally
   4. Car occupants, usually the driver, in 78 percent of cases
   Show answer

   Car occupants, usually the driver, in 78 percent of cases. In large truck crashes, the occupants of a car, usually the driver, sustain 78 percent of the fatalities, and when a car is hit from behind by a truck the results are too often deadly. A car at 55 mph stops in about 130 to 140 feet but a truck needs 400 feet, so never cut in front of a truck or linger in its blind spots.

Source: the Alaska Driver Manual, Control of Vehicle, Following and Speed. This lesson is a plain English summary, not the law itself; where it differs, the manual and the statute govern. Last checked 2026-09-27.