How Overweight Loads Work

Overweight Load Towing Tips

Overweight load towing causes bridge damage. Bridges show signs of wear and tear in the form of fatigue cracks in the structural steel and cracks in the concrete members that hold the bridge up. If state authorities deem a bridge stressed or fatigued, they can list the bridge as "load restricted," meaning that no overweight loads can cross it. If the problem gets even worse, they may classify it as "load posted." This means lowering and posting a new weight load limit for all vehicles. If things get past that point, the bridge may be closed altogether for repairs or even permanently.

Some investigators say that stress from overweight loads may have helped contribute to the bridge collapse in Minneapolis, Minn., in August 2007. Thirteen people died in that accident. In 2000, a bridge in Wisconsin that supports frequent overweight loads collapsed. A federal study found that 18 percent of bridge weight limits are either not posted or are incorrect. The same study found 26 percent of our bridges structurally deficient [source: USA Today].

What overweight load towing considerations should you keep in mind as you traverse roads and bridges? Stress cracks and weight damage can happen on concrete and asphalt -- that's why the specific route is required for submission when permitting and overweight load. So, it's important if you get permitted for a specific route to not deviate from it.

The worst accidents you see on the roads are when an overweight load truck has turned over. Not only is it dangerous because the size of the truck, but there's also a heavy payload now scattered across the highway. A logging truck carrying two dozen full-size trees crashing on a busy highway is way more dangerous to other drivers than a contained, normal-sized load. Overweight loads also make it more difficult to regain control in case of an emergency maneuver. Having the weight evenly distributed on the truck bed is vital to the steering performance, so packing the load is something that's planned out with great caution.

If you're driving on the road in your car, give overweight loads plenty of room to operate and avoid driving in their blind spot. If you pass, do so quickly and give yourself plenty of room to avoid cutting them off after the pass is complete. You shouldn't follow too closely either -- anything within three to four car lengths behind the truck can't be seen by the truck driver.

For more information on overweight loads and other towing challenges, please visit the links below.

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More Great Links


  • "Determine if a permit is required." Wisconsin Department of Transportation. 2008.
  • "Legal Load Limits, Overweight Loads and Pavements and Bridges." 2008.
  • "Oversize Loads - Routing High and Wide." 2008.
  • "Oversize Loads." 2008.
  • Castro, April. "Overweight trucks punish roads, bridges with states' permission." USA Today. Sept. 10, 2007. ­