Towing Education
Weight Distribution Hitch vs Sway Bar: What You Need to Know
If you’ve ever felt your trailer wandering off course or tugging at the back of your vehicle during a crosswind, then you’ve experienced trailer sway.
When you go to search for a solution, you run into a new challenge: search results include two primary solutions, a weight distribution hitch vs a sway bar.
How do you know which one will solve your problem?
Weigh Safe is here to help clear the air.
Below, we discuss the difference between sway control vs weight distribution hitches, misconceptions that trip people up, and how the two solutions work together so you can purchase the right hardware for your setup.
What Is Trailer Sway?
Trailer sway is the side-to-side motion that builds up behind your tow, commonly referred to as fishtailing. It is a swinging motion from side to side, where the trailer pivots on the hitch ball and pulls the rear of your tow vehicle with it.
What Causes Trailer Sway?
Tongue Weight
Tongue weight is the downward force the trailer’s coupler places on the hitch. Your tongue weight should be comfortably between 10 and 15 percent of your loaded trailer weight. The modern towing standard, SAE International’s J2807, uses 10 percent tongue weight as its baseline assumption.
If your tongue weight is too low, there’s too much of the load behind the trailer’s axle, making it more likely your trailer will sway.
When the tongue weight is too high, there’s too much load sitting ahead of the trailer’s axle, making your vehicle harder to control and increasing your braking distance.
In Weigh Safe’s own road test, a trailer loaded with too much tongue weight (20 percent) took 22 percent farther to stop, an increase of 49 feet in braking distance. Getting tongue weight into the correct range is the foundation of stable towing.
Why Does My Trailer Sway Even When It’s Within Weight Limits?
Your total weight and balance are two separate factors. If your trailer load is positioned wrong, your rig may sway because the distribution of weight isn’t even—regardless of whether your vehicle is safely under the weight limit for your setup.
Another factor to consider is if you are estimating tongue weight based on the brochure’s “dry weight”. You need to measure your tongue weight after you’ve added a battery, propane, water, and other gear.
What a Sway Bar Actually Does
A sway bar, or sway control, targets the side-to-side motion of your setup, adding friction between your tow vehicle and trailer. A sway bar typically uses friction plates located at the hitch head or along the trailer frame to introduce resistance that fights a trailer’s pivot and swing.
Does a Sway Bar Fix the Cause of Trailer Sway?
Not entirely. A sway bar helps to manage side-to-side motion, but doesn’t solve the source of the issue: balance.
A sway bar can improve your ride and reduce sway, but it’s important to distribute your trailer load evenly and set your tongue weight correctly in every setup.
A Weight Distribution Hitch: What it Does and How it Works
A weight distribution hitch is designed to help with a different issue, called a squatting hitch. When there’s too much weight on the rear of your tow vehicle, the back end sags and front end lifts. This condition is the result of the setup lifting weight off the front axle, reducing your steering response and braking control.
A weight distribution hitch uses spring arms to relocate tongue weight forward to the front axle and back to the trailer’s axles, leveling the rig and restoring handling.
When Do You Need Weight Distribution?
If your loaded trailer weighs more than half of your vehicle’s weight or the trailer is longer than your vehicle, you likely need weight distribution.
You should check your owner’s manual to clarify the weight of a load that calls for weight distribution and sway control.
Do You Need Both? How They Work Together
For taller trailers like campers and travel trailers, it’s best to have both. Weight distribution levels and stabilizes the rig, and sway control keeps it tracking straight.
A lighter, smaller trailer may not require both. If a trailer doesn’t sag your tow vehicle and isn’t weighed down with a heavy load, you could be fine with sway control alone.
The good news is you don’t need separate components. An integrated system like the Weigh Safe True Tow combines weight distribution with four-point sway control in a single hitch. It also includes a built-in scale that shows your tongue weight directly, so you can confirm your trailer is loaded and set up correctly instead of guessing.
Tow with Confidence
Regardless of the vehicle you drive or trailer(s) you plan to tow, you’ll enjoy a safer, more comfortable ride when you focus on properly balancing your load. By setting your tongue weight properly, leveling your load, and adding sway control, you can tow with confidence and protect the longevity of your vehicle.
With Weigh Safe, you don’t have to choose between better control or weight distribution. If you need weight distribution and a sway bar, our True Tow products have you covered on all fronts. And, with our built-in scale, it’s always easy to be certain about your load setup.
FAQs
Does a 3,000 lb trailer need a weight distribution hitch?
Whether your trailer needs a weight distribution hitch depends on the actual tow vehicle. If the weight of the tow trailer is more than half your tow vehicle’s weight, you should have a weight distribution hitch. Therefore, if you are driving a midsize SUV you probably need one, but a three-quarter-ton truck may be fine without it.
Why does my truck still squat with a weight distribution hitch?
A weight distribution hitch restores the weight getting lifted off the front axle, but isn’t guaranteed to remove all squat. The trailer’s tongue weight is pressing on your rear springs which could still cause some squatting. You are free to use airbags to reduce any remaining squat, as long as you check the weight distribution after doing so, to ensure it is set up properly.
Can you back up with sway control attached?
With many friction-style sway bars, you need to loosen or remove the bar before making tight turns in reverse. Integrated weight distribution hitches with built-in sway control generally let you back up normally without removing anything.
Take all of the guesswork out of every tow with Weigh Safe.
