Choosing a Tow Vehicle for Your Boat

The ability to haul your boat to launching ramps in far-flung places is one of the thrills of boat ownership. But if you’re new to the game, be aware that the correct choice of tow vehicle itself is crucial for safety and peace of mind. Identifying the vehicle you need begins—but doesn’t end—with knowing the weight of the boat you’re about to haul. Here’s an example:

My future boat weighs in at 2,900 pounds, but that’s only one of the elements I need to consider. The trailer weighs another 1,200 pounds and added gear probably means another 600 pounds. Most boat manufacturers don’t provide vessel weights that include that gear, or fuel and water. If you’re pulling a powerboat with a freshwater supply, for instance, figure 6.1 pounds per gallon of gas and 8.3 pounds per gallon of water.

There are more considerations and calculations to make when choosing a tow vehicle than just boat and trailer weight.

There are more considerations and calculations to make when choosing a tow vehicle than just boat and trailer weight.

Since most people head to the water with full tanks, the easiest way to calculate this weight is to expect full tank capacity and add this to the base weight of the boat. This is often referred to as gross vehicle weight rating (GVWR), but again add the trailer weight to this to find out how much total weight you are pulling.

Tow ratings are usually expressed with just the driver on board, so you also have to add the weight of any passengers you might be carrying in the (fully fueled) tow vehicle itself to come up with the all-important Gross Combined Weight Rating (GCWR)—the measure of the max allowable loaded weight for the tow vehicle AND its trailer, including passengers, equipment and gear.

Now that I know the total weight I can zero in on the right tow vehicle. Since a vehicle’s towing capacity is determined by the size, power, and type of engine, and the type, quality, and stiffness of the suspension, along with any additional internal parts such as transmission cooler, oil cooler, turbo, etc., here are some further considerations:

Since I’m planning on doing some high-speed long-distance interstate driving, the vehicle I choose should also have added transmission and oil cooling capacity and a bigger radiator. Fortunately, most “factory” tow package upgrades have these,  along with the receiver hitch, beefed-up suspension, and special heavy-duty wiring harness. What they might not include is a transmission temperature gauge. Automatic transmission failure is almost always due to overheating.

I will choose 4WD over AWD because 4WD offers “low range” gearing via a two-speed transfer case for increased torque when on those steep and slippery boat ramps. I’m definitely staying away from 2WD, especially front-wheel drive, since the weight of the trailer might reduce the traction of the front wheels.

Rather than search each manufacturer’s individual specs for tow ratings I’m going to use the Tow Rating Database  found on Camping to further hone my tow vehicle search. Finally, I’m going to make sure my tow package conforms to all the state laws pertaining to size, weight, and equipment, such as trailer brakes required by all the states I plan to travel through. A good source for this information is AAA’s digest of motor laws.

While I’m resigned to the fact that my tow vehicle may cost more than the boat I pull, I’m getting closer to choosing the tow package for my needs. I hope my search has helped guide your own towing requirements.

A previous version of this article appeared on Boat Trader in December 2012.