How Boat Towing Safety Works

boat towing safety
Boating can be tons of fun -- car accidents, less so. See more truck pictures.
© iStockphoto/ Tim McCaig

While some people are lucky enough to have lakefront or oceanfront property, the rest of the boating community is typically stuck transporting their boats -- often for many miles -- which usually means wheeling out the trailer and hitting the road.

But towing a boat, like all types of towing, needs to be undertaken with care. Seasoned pros might make it look simple, but if you've ever seen a rookie on the road, chances are you've changed lanes and given them a wide berth when possible to avoid the swaying trailer swinging behind them.


There are lots of ways to make a trailer trip safer, like by learning how to brake while towing, how to turn while towing, how to back up towed vehicles and how to avoid jackknifing. When it comes to towing a boat, like many other types of loads, the most important safety precautions you can exercise actually take place before you even stick the key in the ignition

For example, you want to make sure your vehicle can handle the size boat you bought, and this involves a number of calculations and measurements. Then you need to make sure the boat itself is ready to ride, along with the trailer it will travel on. Finally, special care is needed during the packing process, because one poorly placed piece of payload can have your trailer swinging across three lanes of traffic -- or worse.

On the next couple of pages, we'll take a closer look at some of the major trouble spots that should be checked before any trailer trips to the beach with your boat, and some tips for packing as well.



Boat Towing Vehicle Safety Checks

boat towing safety
Your vehicle is going to be working hard -- make sure it can handle the load.
© iStockphoto/ Tim McCaig

First things first, the vehicle that's going to be used to tow the boat needs to be checked out from top to bottom to make sure that it's able and ready for the trip. There are several things you'll want to ask yourself and several calculations you'll want to make before you start throwing the fishing gear into the back and loading up the kids.

One primary consideration is the tow vehicle's total towing capacity. The maximum weight capacity your vehicle can tow -- and just as importantly, the recommended capacity it can tow -- is usually something you can find out from the vehicle manufacturer or the owner's manual.


Next, determine whether the tow vehicle can handle the weight of the boat by getting the dry weight of the boat from the owner's manual. Then, slap on another several hundred pounds for all the fuel and gear you'll probably be hauling along, too. There are a number of components of the tow vehicle that'll be under considerably increased strain while you're towing, and this needs to be taken into account. Make sure the tow vehicle's engine, cooling system, brakes, suspension, tires, transmission and other components are all up to the job.

Don't underestimate the importance of having your hitch system checked out by a professional. He or she might recommend additional equipment like a weight distribution system or a sway control device, and he or she can tell you how much of a load the system can handle and make sure it's in good working order. Knowing how much total weight your hitch can haul -- and how much of the trailer's weight it needs to be bearing itself -- is critical for a safe and stable tow.

If those numbers and systems all check out, the next recommended step is to perform a rundown of your vehicles. A checklist is a good way to go; it helps make sure no important steps slip your mind. There are a number of items that are crucial to examine before every trip.

On the towing vehicle, the brakes, tires and wheel bearings should all be checked for wear and tear and operational soundness. Make sure the mirrors are large enough to give a full view of the rear of the trailer -- you don't want any surprises back there.

Next, we'll take a closer look at your boat's trailer, checking to make sure everything's shipshape before we head out to open water.


Boat Towing Safety Checks

boat towing safety
It's just as important to check your trailer from top to bottom before heading out.
© iStockphoto/ Tim McCaig

Once the vehicle check is out of the way, there are a number of components that need to be looked at on the trailer. One place to start is the electrical system. Have someone stand behind the boat trailer and verify that all the signals are working. Brake lights, blinkers, running lights and brakes should all be checked -- along with the connector between the tow vehicle and the trailer where the wiring passes. Corrosion can be a problem, and the wiring can chafe and short-circuit if not routed in properly.

If the trailer has multiple axles, noticing a flat tire can be a challenge. A good whack with your tire iron can let you know they're inflated, and a quick feel after driving a bit is a good way to tell if one is running hot. Since a flat tire can lead to a fire, nothing beats actually hunkering down and manually checking the pressure of each tire with a pressure gauge to verify their soundness. This should be done before every trip.


Check all the lug nuts and bolts on your hitch and trailer; they can loosen over time through regular driving conditions or rust if they get wet too often. Another issue people towing trailers -- especially boat trailers -- often encounter is problems with the wheel bearings. Wheel bearings warm up during a drive, so if you plunge them into cool water they have a tendency to suck in water as the air inside them cools and shrinks. The outcome is often rust, although spring-loaded pressurized bearing caps can help prevent this from occurring. Bearings can also need a tune-up and some fresh grease if they're running hot.

Many trailers are set up with their own brakes, which mirror the activity of the tow vehicle's movement and brakes. One popular type -- surge breaks -- work automatically. As the tow vehicle slows, the surge brakes kick into action because of the change in forward velocity. Also good are electric brakes, which are hooked up through the connector and sense any pressure on the brake pedal. Especially for heavier loads (and unless you're towing a dinky little rowboat, you probably have what constitutes a heavier load) these types of trailer brakes can be essential. So make sure everything is functioning as it should be before you head out.

Safety chains are attached and secured in a crisscross pattern between the trailer and the tow vehicle to securely hold the trailer in place if the some portion of the hitch should fail. You won't be able to finish out your trip using just the safety chains, but you should be able to safely come to a stop to check out the problem. Breakaway switches are also important components and are often required depending on the weight of the trailer. They work a lot like the emergency clip on a treadmill actually -- if for some reason the tow vehicle and the trailer come apart, the breakaway switch triggers the trailer brakes to come to a stop.

For boat towing, a primary concern is that the mainframe of the trailer can support the boat evenly, and that the boat fits snuggly and securely into its cradle. Hull rollers and pads need to be in good shape so they don't scratch the boat. An appropriate number of straps and ties need to be checked, adjusted and fastened properly so the boat is fully lashed down.

Your checklist is checked for the truck and the boat, and eager travelers have been piling up their luggage in the driveway. But chucking everything in willy-nilly would be about the worst mistake you could make at this point. Unfortunately, you still have a quite a chore ahead of you -- packing the boat so the weight is distributed evenly.


Boat Towing Weight Distribution

boat towing safety
Before you hit the road, make sure everything is properly loaded and strapped down for the drive.
© iStockphoto/ Tim McCaig

When you get to the point where the vehicles are all checked out, you can focus your attention on loading. The two main rules of thumb for loading a trailer are: keep the weight of the load balanced both front to back and side to side, and maintain a low center of gravity. Because of this, loading boats can be a little different from loading regular trailers -- you have fewer options for where to place the weight since a lot of the heavy items are in predetermined locations, like the motors and engines. This is another reason why boats must be supported evenly by the trailer; it helps distribute the weight of the hull, engine and equipment in a safer fashion.

It may sound silly, but one important step in loading a boat is to make sure there isn't any trapped rain or other water stowing away on your boat. Water runs about 8 pounds (3.627 kilograms) a gallon, so if stormy weather recently passed through town, it may have thrown your weight calculations way off.


It's good when you're loading a boat, especially for the first time, to use a special scale to measure the amount of weight going on the hitch (i.e. not a jerry-rigged system that uses the little scale in the bathroom but one actually designed to measure thousands of pounds of weight). This can help you adjust the boat's position to make sure about 10 to 15 percent of the weight is on the hitch, because more or less can decrease stability and be dangerous. You can also use additional cargo to help balance the weight properly. If you do a bad job, the trailer may experience two dangerous phenomenons you never want to encounter: dive and sway. For more information on dive, sway and for tips on trailer weight distribution, check out How to Load and Unload Towed Vehicles.

Dual axles and weight ­distributing systems both can help make towing a boat safer. With two axles on the trailer, not only does this usually make a flat tire a little less harrowing, it also means you'll have an easier time distributing the load. A weight distributing system can also make loading easier, because it can spread around any extra weight that can't be handled by the hitch, moving a portion of it off the hitching system (and in turn the rear axle of the tow vehicle) and onto the front axle of the tow vehicle and the axles of the trailer.

There are a number of local and state regulations that concern boat towing, and once you arrive a­t the lake or the beach, what's the best way to launch your boat? To learn more about these topics, check out articles like Launching a Boat, as well as the links on the next page.


Lots More Information

Related HowStuffWorks Articles

More Great Links


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