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Sorry, don't think you'll be going this fast! Unlike the big rigs, if you have to tow something like a boat, horse trailer or car -- you're going to be taking it a bit slower. See more truck pictures.

© iStockphoto/The Tor

Introduction to How to Tow at the Maximum Controllable Speed

No matter how much the kids are screaming and the wife is glaring, the answer to "Are we there yet?" while taking a trip with a trailer doesn't mean you can just give it a little more gas. Towing a trailer is tricky business, and more speed makes it all the more complicated.

So what makes driving with a trailer so challenging? A number of factors can play a role, but the most basic items to consider are the increase in overall weight and the connection between the vehicles. If you add ingredients like heavy traffic or high winds to the mix, there's definitely the potential for trouble. And while you can't control the traffic or the weather (although you can pull over and wait for them to improve), one thing you can control is your speed.

It may take longer to safely accomplish driving maneuvers with a trailer, but since other drivers' (not to mention other passengers' and pedestrians') lives are on the line, hitting the road with a trailer isn't a free-for-all, and speed takes a back seat.

That being said, just how fast is the max? On the next page, we'll discuss some recommended speeds for towing.

With one of these connecting two large coupled vehicles -- there's only so fast you can go and stay safe.

© iStockphoto/Dan Driedger

Recommendations for Towing at Maximum Controllable Speed

The truth is there's no speed below which everything is peachy keen and above which disaster is certain to strike. But there's definitely a zone that's considered safer and a threshold where things start to get dicey.

The maximum controllable speed (or maximum open road speed) is the speed at which an outside factor, maybe a gust of wind or the need to make a sudden maneuver, will cause a vehicle to go out of its operator's control. There's not a way to set a precise mile-per-hour limit though, because the maximum controllable speed depends on a couple of big variables -- namely the vehicle, the driver and the driving conditions.

For example, if you're just setting out on a tow, take it easy and test the waters. A bad packing job might mean the maximum controllable speed your trailer can handle is lower. If it's a gorgeous day and you're an old hand at towing, you can probably muster the trip a little faster. Bumpy old roads mean you have to slow down, so does the company of big trucks and cross-currents. Every time you see your trailer start to sway, ease off the gas until it straightens out.

It's also important to keep in mind there may be government regulations in place that limit how fast you can drive with a trailer. Before you head out, you'll probably want to check out the rules and regulations enforced by local transportation agencies to avoid a ticket.

For example, if the HowStuffWorks crew decided to spend an afternoon boating at a nearby lake, our only guideline for how fast we could drive to get there would be the posted speed limit and the trailer-towing skills of whoever was doing the driving. If we were boating in, say, New Zealand, we would be legally limited to between about 50 and 55 mph (80 to 90 kph) even if the highway signs said something higher. U-Haul recommends a maximum speed of 45 mph (about 75 kph) for users of their rental towing equipment [source: U-Haul].

So just remember, no matter how badly you want to get where you're going, anyone with experience in towing will tell you that's a recipe for disaster. Towing calls for care and concentration, not quickness.

For more information on planes, trains and automobiles, see the links on the next page.

Lots More Information

Related HowStuffWorks Articles

More Great Links

Sources

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  • "California Driver Handbook." California Department of Motor Vehicles. 2008. 9/19/2008) http://www.dmv.ca.gov/pubs/dl600.pdf ­
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