What You Need--and Need to Know--to Properly Tow a Trailer

Towing a trailer or boat is not as simple as hooking it up to your vehicle and toodling down the highway. When you have a couple thousand pounds of potential missile sitting behind you, you need to know how to properly set up both tow vehicle and trailer to keep you, your passengers, and people driving near you safe. All it takes is some knowledge and a few upgrades, which is what this article is about. Let’s get to it, shall we?

Towing Capacity
The best place to start is determining your vehicle’s towing capacity, which is the maximum weight capacity your vehicle can handle as determined by the manufacturer. If you exceed its towing capacity by even a small amount, steering and braking will be adversely affected.

The Curt Manufacturing website goes into great detail on all the various weight ratings that determine towing capacity. All are important, but there are a couple you should pay particular attention to:

Gross Vehicle Weight Rating (GVWR) is the maximum weight of your vehicle with passengers and cargo, but no trailer. It is the starting point for determining how heavy a trailer you can safely tow. GVWR is also used to rate the maximum weight of a trailer, including load.

Gross Combined Weight Rating (GCWR) is simply the weight of both the tow vehicle and the trailer together, including passengers and cargo. The vehicle manufacturer bases this rating on the strength capacity of the vehicle’s frame, suspension, axles and other components.

Gross Trailer Weight (GTW) is the actual measured weight of a trailer with cargo. GTW should never exceed the trailer’s Gross Vehicle Weight Rating (GVWR) as stated by the manufacturer. Trailer hitches are rated by GTW.

Tongue Weight is the downforce a trailer puts on the rear of the tow vehicle. Too much tongue weight will cause the rear of the trailer to sway and make the tow vehicle difficult to control. Tongue weight should not exceed 200 pounds for trailers up to 2,000 pounds. Tongue weight for trailers over 2,000 pounds should be 10 to 15 percent of the trailer's loaded weight. 

Curt makes a handy device called the BetterWeigh Mobile Tow Scale to accurately measure GCWR, tongue weight, and other parameters and tell you if your vehicle is overloaded or if weight is properly distributed for safe towing.

Choose the Right Hitch
Once you know your towing capacity, you can select the correct trailer hitch for the job. The most common type is the receiver hitch that mounts to the tow vehicle. Receiver hitches are classed by Gross Trailer Weight (GTW). You want a hitch rated for more than the total weight of your trailer and cargo:

• Class 1: up to 2,000 lbs. GTW
• Class 2: up to 3,500 lbs. GTW
• Class 3: 3,500 to 12,000 lbs. GTW
• Class 4: 8,000 to 14,000 lbs. GTW
• Class 5: 16,000 to 18,000 lbs. GTW

Once you choose a hitch, you will need a hitch ball, ball mount, and a hitch pin. If your trailer did not come with a coupler that connects the trailer to the receiver hitch ball, you will need to get one of those too.

Other types of hitches include: 

• An adjustable hitch is actually a type of ball mount that fits in a receiver hitch. They can be adjusted for height to accommodate trailers, cargo racks, bike racks, etc. Some come with different-size balls to fit a variety of trailers
• A weight distribution hitch distributes the tongue weight of a trailer across the vehicle and trailer for better control. It fits in a standard receiver hitch
• Gooseneck and fifth wheel hitches mount in a pickup truck bed. You'll find these hitches on large travel trailers and car haulers
• A pintle hitch uses a hook and ring mechanism to attach a trailer to the tow vehicle. They are very strong and common for industrial and agricultural use

We strongly recommend getting a set of safety chains or cable to keep the trailer connected to the tow vehicle if the hitch fails. Two safety chains should be used, crossed under the trailer tongue with enough slack for turning.

Trailer Upgrades
Dedicated trailer tires and wheels are safer than using castoffs from your truck or car because they’re designed to meet a trailer’s load and handling requirements. Many aftermarket wheel companies make trailer wheels that match their truck wheels so you can look snazzy rolling down the highway.

Replace old or broken trailer lights with bright LED lighting so you can see—and be seen—better. LED lights use less power than other types of lighting, which takes some of the stress off of your wiring harness. Since you’re already in there, it would be an excellent idea on your part to inspect and update your trailer wiring if necessary.

A trailer wheel hub odometer records your trailer’s actual mileage, just like a vehicle odometer. It can make scheduling maintenance easier since you can base it on actual mileage.

Timbren Axle-Less Trailer Suspensions are like an independent suspension for trailers. They replace the trailer’s solid axle with progressive-rate main springs to absorb road shock and support the trailer's load while delivering a smooth, stable ride, regardless of load size. They even have built-in camber and toe-in to help your trailer to track straight and reduce tire wear.

Here are some other trailer upgrades that are worth considering:
• Trailer storage boxes
• Receiver and coupler locks
• Ramps

Tow Vehicle Upgrades
If your tow vehicle does not have one from the factory, one of the best things you can get to make towing safer is a trailer brake controller. It allows you to activate, adjust, and monitor electric trailer brakes from inside the vehicle. Time-delay controllers apply power to the brakes over time in a user-selectable ratio. They are a good choice if you use different trailers as you can easily adjust the ratio for each one. Proportional or inertia-based controllers apply power in proportion to the vehicle's deceleration. That means smoother stops and more efficient braking.

Suspension upgrades like rear air bags and helper springs will improve your truck’s cargo capacity and help prevent sagging and swaying when towing a heavy trailer. Air bags are adjustable, allowing you to level the vehicle front to back and side-to-side to compensate for varying loads and trailer weights. You can get anything from a simple pair of air bags to complete systems with onboard compressors and wireless controllers.

Helper leaf springs are super-simple and maintenance-free, and some are adjustable for uneven loads. If you want to get fancy, the Roadmaster Active Suspension System takes the helper spring concept one step further by adding a coil spring under tension to absorb loads rather than resist them. That improves stability, balance, and driver control without compromising ride quality.

A backup camera is invaluable when backing up with a trailer or trying to hitch a trailer to your vehicle. You can also keep an eye on the trailer while in motion to make sure everything stays connected.

Towing Tips
Load your trailer properly. Ideally, you want at least 60% of the cargo weight at the front of the trailer for safe handling with less chance of fishtailing. Make sure cargo is properly secured, especially in an open trailer. When you make a stop, check the cargo to make sure it hasn’t shifted or broken loose.

Give yourself more time to slow down by increasing the space between you and the vehicle in front. Don’t speed and avoid sudden acceleration, panic braking, and maneuvering.

Since it takes longer to accelerate, stop, change lanes, and turn with a trailer, scan the road ahead farther than you normally would. You can see many situations developing a long way off and prepare accordingly.

Make wider turns at curves and corners. Because your trailer’s wheels will end up closer to the inside of a turn than the wheels of your tow vehicle, the trailer tires are more likely to hit or ride up over curbs.

Be extra careful when changing lanes. Make sure you have plenty of space and move slowly from one lane to the other. Summit Racing carries towing mirrors from CIPA and K Source that provide a wider view of what’s behind and to the side of you to reduce blind spots.

Drive in the right lane on four-lane highways as much as possible so you can use the shoulder for extra stopping room if needed. Driving in the ‘slow’ lane also makes it easier to move onto the shoulder in case of a tire blowout.

Don’t ride your truck’s brakes on long downhill stretches. Shift the truck’s transmission to a lower gear to help slow the vehicle. Apply the brakes at intervals (aka pumping) to keep speed in check and the brakes from overheating. Many of today’s pickup trucks have a tow/haul mode that will automatically downshift the transmission when it senses the truck is on a long downhill stretch.

Adjust trailer brakes according to load. For example, if the brakes are set for a fully loaded trailer, you will need to readjust them when towing the trailer unloaded to prevent the trailer’s tires from locking up and skidding.

Know your trailer. A loaded trailer will often weigh more than the tow vehicle, which will have a huge impact on the truck’s ability to stop quickly and navigate sharp turns. Become well-acquainted with trailer’s length, width, and height, especially if it’s a large car hauler or a travel trailer. You want to avoid issues with low bridges and tight parking areas.

Resources
We turned to Curt Manufacturing’s Towing 101 guide for a lot of the information in this article. It’s divided into sections that explain things like towing capacity, help choosing and installing a hitch or brake controller, and advice on how to tow safely. It’s a great place to start your towing education.