How Trailer Towing Safety Works

Trailer Towing Driving Safety

Remember to maintain your equipment and be safe on the road.
Remember to maintain your equipment and be safe on the road.
Jill Fromer/iStockphoto

If you take nothing else away from this article, please remember this: Practice is critical. If you're new to towing, you'll need to get some practice under your belt before hitting the road. Your vehicle will respond differently when towing a trailer than it will on its own. Even a simple task like coming to a stop takes practice. If at all possible, practice towing a trailer in a large area like an unoccupied parking lot.

If you're towing a trailer that has a wider wheel base than your tow vehicle, you may need to replace your normal side view mirrors with a larger set or use mirror extenders. These will give you a better view around the sides and even allow you to see behind the trailer. In the United States, several states require you to use extenders if you're pulling a trailer over a certain size.

A wider trailer also means you have to be careful when making turns. The trailer's wheels will be closer to the edges of the curve. If you're not mindful of the difference, you risk hitting a curb or other object, which could cause damage to your trailer's wheels and axle. So remember to allow extra room when you're turning while towing.

You should always be particularly careful when you are accelerating and braking while towing. Remember that by towing a trailer, your vehicle has much more mass than normal. This mass has momentum and inertia. Inertia is the tendency for an object to maintain its current state of momentum -- or motion -- without interference from an exterior force. An object with more mass will also have greater momentum and inertia. That means your tow vehicle will have to work harder when pulling a trailer -- the added mass requires more energy to move and stop.

Because your vehicle has to work harder to accelerate and brake, it's a good idea not to drive too fast. Speeding will put more wear and tear on your vehicle. Your engine will have to work harder and it could also put a strain on its suspension, brakes and other systems. Also, you'll need more room to slow down or come to a stop. You shouldn't follow other vehicles too closely -- you won't have time to stop if something goes wrong.

Another reason not to speed is because it can cause trailer sway. Trailer sway is a very dangerous situation. Together, a tow vehicle and trailer create an articulated vehicle. That means one section of this overall vehicle (the point where the coupler and trailer hitch meet) is flexible to an extent. If it weren't, you'd have a hard time making turns. But being articulated also means that the rear of the vehicle can move somewhat independently of the front. That's the basis of trailer sway.

A trailer may begin to sway back and forth if the load inside it isn't balanced properly, if a gust of wind hits it or during acceleration (particularly if the vehicle is traveling downhill). At first, the sway may be minor. But under certain conditions, the sway could get worse -- the trailer begins to move back and forth, gaining momentum on each swing. Unchecked, the trailer could cause you to jackknife. Or it might cause you to lose control of the tow vehicle and have an accident.

Trailer sway can be terrifying and difficult to correct. The best way to solve the problem is to apply the trailer's brakes (but not the tow vehicle's brakes) and come to a gradual stop. Don't try to steer out of it -- you'll just magnify the situation. Once off the road, try balancing the trailer load. If that doesn't solve the problem, stop driving and call for help -- trailer sway has led to several accidents, some of them fatal.

With the right approach and equipment, you should be able to tow a trailer safely to your destination. Remember that the important thing is to practice and keep a level head. And have a good trip!


To learn more about towing, take a look at the links below.

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More Great Links


  • Allen, Mike. "Saturday Mechanic: Wiring Your Trailer Hitch." PopularMechanics. Feb. 2004. (Sept. 24, 2008)
  • AON Recreation. "What You Need to Know to Tow." 2007. (Sept. 22, 2008)
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  • Tools of the Trade. "Towing Safety." Tools of the Trade Magazine. Nov. 1, 2006. (Sept. 23, 2008)
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  • National Highway Traffic Safety Administration. "Towing a Trailer." April 2002. (Sept. 24, 2008)