What Size Weight Distribution Hitch Do I Need?

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If You just bought a trailer and want to be safe towing a trailer, you might aske yourself, what size weight distribution hitch do I need?

Weight distribution hitches should match or exceed the Gross Trailer Weight of the trailer. If you have a trailer that weighs 6,000 lbs, and the tongue weight is around 650 lbs, then you would need a weight distribution hitch rated for 7,000 lbs and 700 lbs of tongue weight or more.

Millions of Americans pull loads daily on light-duty trailers hooked to the back of a tow vehicle. While most towing experiences happen without incident, the NHTSB reports that some 21,000 accidents involving faulty hitches or hitching practices occur annually. (450 deaths yearly occur in accidents with tow vehicles and small trailers). A weight distribution hitch can be an essential tool to help increase your odds of not being in an accident. But what size is right? How do you know if the hitch you purchase will do the job? Well, let’s explore that question for a minute.

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What Is a Weight Distribution Hitch?

A weight distribution system balances a load of a trailer more evenly than a conventional trailer hitch. The hitch distributes the trailer weight over the four wheels of the tow vehicle, by reinforcing the trailer tongue weight. They help provide a smoother ride for the tow vehicle by lightening the load of the tow vehicle’s rear axle. Since the trailer weight spreads over a larger area, this weight distribution hitch system makes for safer towing.

Whenever you hook up a trailer to a tow vehicle’s hitch, there is weight from the trailer’s tongue exerting a downward force on the back of the tow vehicle. (If you have ever seen a bumper sag when a trailer is attached to it, you’ve seen evidence of a trailer’s tongue weight). If there is too much weight, the back of the truck is heavier than the front, and the trailer pushes the load (rather than the tow vehicle pulling it). A weight distribution hitch counters this by providing additional support (spring arms), which keeps the rear axle from sagging. (A tow vehicle with a heavy rear end may not brake or steer properly). The hitch is designed to prevent trailer sway by shifting more weight to the front.

How Does A Distribution Hitch Work?

A weight distributing hitch hooks to a hitch receiver like any standard ball, but with the addition of two spring arms that extend toward the trailer’s tongue. Because these bars are connected to the trailer frame, they exert a downward force on the trailer, lightening the load placed directly onto the ball by the coupler. This effect is an opposing force to the trailer tongue’s weight. The back of the tow vehicle carries less weight, allowing the front axle of the tow vehicle and trailer wheels to share some of the load.

A weight distribution hitch fits into a receiver hitch just as a standard ball mount would. On top of the hitch, you will find a recognizable hitch ball where the trailer coupler will sit. Two spring bars that hook to the trailer tongue extend from the WD hitch. There is a bracket with a couple of bolts that unscrews to fit around the bars of the trailer tongue (frame). Once connected, the stabilizer bars act as a lever, pushing up against the trailer's weight. The more level the towing connection is between the tow vehicle and trailer, the easier it is to tow and the safer the ride.

What Weight Distribution Hitch Size Do I Need?

The correct size of the weight distribution hitch should match or slightly exceed the Gross Trailer Weight rating and the Tongue Weight (the maximum weight capacity). For example, if you have a trailer with a GWR of 4900 lbs and a tongue weight rating of 500 lbs, you need a 600/6,000 lb WD hitch. (Remember that manufacturers do not include add-ons like generators, batteries, and propane tanks that sometimes ride on the tongue and add to its weight).

According to etrailer.com, you want your total tongue weight (tongue weight plus cargo) fall in the middle range of your WDH range. For example, if you have 1,000 lbs of total tongue weight, then a weight distribution hitch range of 800 - 1200 lbs is suitable.

Your owner’s manual or many online sites can help you determine the size of the weight distribution system you need, or a simple call to your local trailer dealer can also provide you with the information.

When Do I Need to Use a Weight Distribution Hitch?

Most half-ton trucks on the market suggest using a weight-distributing system when your trailer weight exceeds 5,000 lbs. A general rule of thumb is using a WD hitch whenever your loaded trailer and tongue weight exceeds more than 50% of the tow vehicle’s weight. If your manufacturer has printed maximum weight limits for the truck or SUV you use, follow their recommendations. If you exceed them, your insurance company will want to know how much weight you were carrying, and if the weight was loaded correctly. It might have reason enough not to cover the repair cost if you lose control.

A lot of rental and boat trailers come with surge braking systems. Most chain-style WD hitches are not compatible with these systems, so be sure to use a weight-distribution hitch that clearly states that it can be used with a surge brake travel trailer.

Are There Different Types of Weight Distribution Hitches?

There are two types of weight distribution hitches that are sold on the market based on the kind of spring bars used.

A trunion bar hitch fits into the hitch by sliding into the head. Since they connect to the hitch in a more horizontal manner, there is greater ground clearance than a standard round bar hitch. While most trailer owners prefer trunion bar hitches for heavier loads, the load limits between the two depend on the manufacturer and their ratings.

A round bar weight distribution hitch is named for the shape of its spring bars, and that they are rounded in the bend that extends just under the tow hitch. Round bar hitches have a tongue weight distribution of 600 to 1,200 lbs.

Can I Tow More With A Weight Distribution Hitch?

Most weight distribution hitches are built to handle a maximum amount of lbs (depending on the rating). While they can help stabilize a load, they will not let you haul more weight than your trailer or truck can carry. If you tow with a truck with a max towing capacity of 10,000 lbs, it is best to stay under that amount to be considered safe.

Can You Have Too Big of A Weight Distribution Hitch?

The answer is yes. If the WD exceeds the maximum gross weight rating of the trailer. Too much weight distribution can contribute to undue pressure on the braking systems and axle failure.

These kinds of scenarios can lead to accidents.