A weight distribution hitch is a towing system that can help to stabilize the weight of a trailer. If you’ve ever driven an unbalanced trailer before, you might already be familiar with the unpleasant driving experience of having a heavy load pitching, swaying and threatening to tip over while you’re at speed on the road.
Towing a trailer that is seemingly on the verge of pulling your vehicle out of control is a very dangerous, and not to mention nerve-wracking, way to spend what should have been a pleasant vacation. One easy way to improve the safety, driving comfort and even the load capacity of your towing system is by adding a weight distribution mechanism to your hitch.
A weight distribution hitch is also called a load equalizing hitch, and it offers a set of advantages over the standard tow hitch in terms of keeping a trailer aligned and in control.
What Can It Help With?
A weight distribution hitch uses spring bars and extra brackets to counteract the movements that a trailer can make while on the road. Once properly setup, the weight distribution system of these hitches can dampen the up and down motion of a semi-trailer, which can immensely help rein in the dips and lurches that a trailer can make when the driver brakes or accelerates.
The same setup also helps to keep the trailer stay aligned with the towing vehicle, which eliminates excess side to side motion. This feature, in turn, removes dangerous side to side swaying and shifting which often happens when the towing vehicle tries to take the trailer through a curve.
A weight distribution hitch can also help eliminate the potentially dangerous tilts and sways that usually happen when the setup passes trucks and large vehicles going the opposite direction. A setup like this also makes your trailer easier to control in the case of strong crosswinds, as well.
Weight distribution hitches are meant for medium to heavy duty towing, and you will only find them made for Class III, Class IV or Class V tow hitches.
What Does A Weight Distribution Hitch Do?
A weight distribution hitch system does just what it says on the label – it helps distribute and balance out the weight of the trailer in a way that ensures the stability and safety of the whole setup.
In order to understand what a stable towing setup looks like, it’s always a good idea to have a deeper understanding of the different load weights and limits that factor into the overall balance of your trailer, towing system, and your towing vehicle.
What’s The GTW Rating?
The first and perhaps the most important consideration when setting up a towing system is the gross trailer weight, also known as the GTW of your setup. The GTW is simply the gross total of the whole trailer, the contents it holds, and all the additional hardware you’ve installed on it.
This means taking the account everything – the gross weight of the trailer itself, the weight of the cargo, the extra weight of fuel (if you are towing an RV, for example), passengers, luggage and anything else carried in the trailer.
The relationship between the gross trailer weight and the towing system is a fairly simple one – your towing system has a maximum towing capacity, and you generally want to make sure that your trailer load is well within that load limit, ideally with a good deal of headroom.
Knowing the towing capacity of your system is usually a simple matter of checking the information card on the tow bar itself, or looking it up in the manufacturer’s manual.
Your Vehicle’s Towing Capacity:
Then there’s the matter of how much your vehicle can tow. The towing vehicle of your choice has its own towing capacity, which is more of a rating that takes into account a variety of other measurements. To look up the towing capacity for your vehicle, your best bet is to contact your dealer or the manufacturer.
You can also try to look up the information specific for your vehicle model in your owner’s manual, but getting in touch with your manufacturer may also net you a few tips on how to set up your towing system in a way that is safe and will not void any of your repair warranties.
GVWR & GCWR Considerations:
The towing capacity of a vehicle is determined from a combination of several ratings. The first of them is the gross vehicle weight rating or GVWR – this is the maximum weight capacity that your truck or car can carry without a trailer, that is, the combined weight of passengers and luggage you can safely load in it.
Some manufacturers may also specify a gross combined weight rating or GCWR. This rating is the maximum weight capacity of the vehicle, this time with a fully loaded trailer taken into account. These ratings, combined with other ratings like the maximum payload capacity, curb weight and payload capacity of a truck, all go into a formula that determines the towing capacity of a vehicle.
Of course, you likely understand at this point that you should never tow a load beyond the lowest towing capacity of your towing system. If your car can only tow 3,500 pounds, then obviously you will not be able to pull a 5,000 pound trailer even if you have the heaviest duty towing hardware installed.
Along the same idea, you can’t expect your half-ton truck with a towing capacity of 15,000 pounds to be able to safely tow the same load using a Class I tow hitch rated for a maximum load of 2,000 pounds.
Even if you have a good idea of the maximum tow capacity of your setup, the actual load your setup can comfortably carry in practice is another thing altogether.
What Weight Distributing Hitches Help With…
If your trailer starts to approach the maximum tow capacity of your tow hitch system, then you start to run into driving comfort issues – your setup becomes somewhat harder to stop, or it becomes a bit dangerous to bring around corners. You may find that you have to drive at a much slower speed to maintain a comfortable control over your vehicle.
A weight distribution hitch system keeps these issues in check and helps to maintain the ability of your vehicle to accelerate, steer and stop. The weight equalization features of these kits may not be able to drastically improve the actual maximum towing capacity of your tow vehicle, but they can significantly improve the load you can safely tow on the road.
With a weight distribution hitch, you can tow a heavier or larger road in a wider range of road conditions, or you can tow the same load at a higher speed and get to your destination a bit sooner.
One of the more important ways that a weight distribution hitch can help you tow heavier loads safer is by keeping the trailer horizontally level with the tow vehicle, even as your tongue weight goes up to the higher ranges of what your tow setup can safely carry.
The tongue weight or tow ball weight is the actual weight that the tow ball of the hitch actually carries – if your trailer is front-loaded such that some of the load is nearer the tow link, you might have a higher tongue weight than is necessary.
The tongue weight is another important measurement you need to consider to keep your setup safe, and towing equipment manufacturers generally recommend that owners keep the tongue weight within 10 to 15 percent of the gross trailer weight.
Even if you keep your tongue weight within this limit, though, you may have a situation where your trailer load is simply too heavy that your trailer can cause a dip anyway. In this case, a weight distribution hitch will shift the load point enough for the whole setup to sit level in most cases. This allows some of the weight to be more evenly balanced such that the front axle of the towing vehicle takes more of the load off of the rear axle.
This will greatly improve the driving of your setup, as your vehicle handles better, accelerates better (especially in the case of front wheel drive cars) and brakes smoother.
What Does A Weight Distribution Hitch Look Like?
A weight distribution hitch looks like a regular tow ball mount setup with the addition of two spring bar arms. At the bare minimum, a weight distribution hitch system has five main parts.
You have the receiver or tow bar hitch that is installed to the frame of the towing vehicle. Then you have the weight distribution shank that slots into the former, which ends in the weight distribution head assembly.
The weight distribution head connects the two spring arms together, and the spring arms in turn hold the frame brackets.
The trailer coupler goes on to the frame brackets, as supported by the movable spring arms.
Many weight distribution hitches come in a complete kit that includes their own trailer hitch receiver. If you have an existing tow bar hitch, then you have to check that you have a compatible 2 inch receiver that can take a Class III to Class V shank.
The weight distribution shank slots into the tow bar hitch receiver to form an attachment point for the rest of the weight distribution hitch, starting from the weight distribution head assembly.
Model Specific Hitches:
If you have a hitch kit that is specifically designed for your vehicle model and your trailer, then chances are good that the included shank will have the perfect rise height to make the whole setup level.
You may find that your tow vehicle or your trailer may need a different rise or drop, in which case there’s no need to panic – there are aftermarket weight distribution shanks you can buy separately, in a wide variety of heights or drops, and one of them may be able to get your setup to the perfect height you need.
The weight distribution head assembly is part of what makes a kit different from others on the market. Many of them will have additional parts and features, but they have all the basic parts in common.
You have the hardware that attaches to the weight distribution shank, as well as a mounting slot for the tow ball. In addition to the larger tow ball, many heads will also have mounting points for smaller hitch balls for friction sway control bars. Some head assemblies will only have one on the right side, while others may let you add two sway control bars for better sway control.
The weight distribution head has mounting points, usually at the bottom, for two spring bars. It is these spring bars that supply the leverage that lets the hitch distribute the load. Spring bars come in different shapes and sizes, and each option comes with its own advantages and disadvantages.
Round spring bars are the most common type of bars you will see, and they generally cost less than other types. They slip under the head assembly via bent tips that are secured by clips, so they tend to lower the ground clearance of the whole kit.
They are also better suited for relatively lighter loads. Trunnion bars, on the other hand, slot in sideways and thus offer higher ground clearance. They can also be used for heavy duty towing applications.
Some weight distribution kit manufacturers use specialized shapes for their systems, and you will often see square bars and other uniquely shaped spring bars designed to work with specialty kits.
A Note On Some Of The Options Out There…
Not all weight distribution hitch systems offer sway control. In the case of kits that do not offer them, you will usually find the standard chain and bracket hardware used. Some of the more premium kits do away with the chains altogether in favor of L-shaped brackets, and they are some of the easiest kits to install since there is no chain that needs length adjustments.
Some top-end weight distribution hitch kits feature dual cam systems, and they can give you the best sway and dip control you can get. On the other hand, dual cam systems are much harder to install – you may need to consider getting a professional to install these kits for you.