Ask a Trooper: How much distance should be between cars?

Published 8:22 pm Wednesday, January 31, 2018

Ask a Trooper by Troy Christianson

Question:  What is the correct following distance? Everyone seems to be way too close behind each other. 

Troy Christianson

Answer:  The only law regarding following distance pertains to vehicles pulling trailers. This includes trucks as well as semi-truck tractors with trailers. They must maintain a minimum distance of 500 feet.

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While state law does not require a specific distance for vehicles not pulling trailers, it does say that you shall not follow another vehicle more closely than is reasonable and prudent, having due regard for the speed of such vehicles and the traffic upon and the conditions of the highway.

We recommend the three-second-plus following distance rule. Watch the vehicle in front of you. When that vehicle gets past an object such as a sign, pole, bridge, etc., then count off three seconds.  You should not arrive at that spot sooner than your count to three. If you do, you are following too close. Also, you must add one second for every hazard that exists. Hazards include, but are not limited to, heavy traffic, rain, snow, fog, driving into the sun, etc. In some cases, you might have to allow six or seven seconds (or even more) to be safe because of existing hazards.

When following a snowplow, it is recommended that you maintain a distance of a minimum of 10 car lengths. It is important to keep your distance to avoid whiteout conditions that may be caused by the snowplow.

Crash facts show a much larger number of cars and pickup trucks being involved in fatal rear-end crashes than semi-truck tractors pulling trailers.

You can avoid a ticket — and a crash — if you simply buckle up, drive at safe speeds, pay attention and always drive sober.  Help us drive Minnesota toward zero deaths.

If you have any questions concerning traffic-related laws or issues in Minnesota, send your questions to Sgt. Troy Christianson, Minnesota State Patrol, at 2900 48th St. NW, Rochester, MN 55901-5848; or reach him at Troy.Christianson@state.mn.us.

Troy Christianson is a sergeant with the Minnesota State Patrol.