Things I Didn’t Know

An empty truck takes twice as long to stop as a full one. From 55 mph, a cargo-laden, 80,000-pound truck requires more than the length of a football field to stop on dry pavement. But the stopping distance doubles for an empty truck under the same conditions. “The braking systems on big rigs require both friction and traction,” explains Durant. “With an empty trailer, the braking capacity diminishes, and you lose traction. The rig could begin to bounce, or it might jackknife.

The whole piece, which contains a few other survival tips for driving among big rigs, is here.

This entry was posted on Monday, June 8th, 2009 at 9:30 am and is filed under Things I Didn't Know. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

5 Responses to “Things I Didn’t Know”

  1. Dale Says:

    I am surprised the article didn’t mention that a truck will travel about twice it’s length before the driver will hit the brakes. So in reality it takes around four football fields to actually come to a complete stop while loaded. ABS brakes may have shortened that slightly, but they mostly keep the trailer behind the truck.

  2. Nancy Says:

    This snippet from the article is for the guy who doubted my story about being tailgated by trucks going down mountains:

    “The difference [in horsepower] also helps explain why you sometimes see a truck’s grille filling up your mirror and tailing you much too close for comfort, especially on downgrades. The truck driver is probably trying to gather speed for the next upgrade. Unfortunately, you can’t do much under these circumstances except to understand the big rig’s limits and get out of the way. “The margin of safety to the rear is the hardest to control,” says Ward. “It’s probably best to change lanes, slow down slightly and let the truck pass.”

  3. Jack Says:

    I too have been tailgated by trucks and had to raise my speed to 95 mph on long downhills to stay ahead by just a few feet. My wife woke up from her nap once and thought she was in a nightmare as another truck was passing on the right… must have been empty as his rear was swinging back and forth wildly. You can’t change lanes and slow down when another truck is blocking the right lane and speeding too. Our growing dependence on just-in-time shipping is lowering our safety and quality of life so a few can save a few more dollars.

  4. Richard Says:

    Trying to take advantage of the downhill is not justification for speeding, nor is it for tailgating. “The difference[in horsepower]” has nothing to do with your ability to brake.

  5. Nancy Says:

    When I was growing up, trucks had a 55 MPH speed limit on roads where the rest of the traffic could go 65. I never see these dual speed limits anymore, but I think they’re needed on these mountain roads.

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