Towing season is upon us and it’s time to hitch up the boat trailers, campers, car trailers or toy haulers. Road trip!
Let’s tap the brakes, though, for a minute and look at what goes into towing safely and comfortably. Regardless of how large or small, heavy-duty or light-duty your tow vehicle is, there are some basic concepts that have to be thought through before pressing it into tow duty.
Tow Capacity – Every vehicle is rated to tow a certain amount of weight, some more than others. My 2012 F-350 is rated to tow 12,000 pounds, my 2014 Wrangler 2-door just 2,000. Unfortunately, this is where many people stop their assessment of vehicle capability and whether or not it’s suited to the job. The problem is that manufacturers, especially in the truck and SUV market segments, have a sales incentives to make those numbers as large as possible without inviting liability lawsuits. So take their numbers with a grain of salt and remember that being able to tow a certain amount of weight and being able to control it are two very different things. A typical tractor-trailer can weigh 80,000 pounds, with most of that weight in the trailer and cargo. But the tractor can’t always control it and that’s why we see jackknifes and roll-overs. The same concept applies to your tow setup.
Let’s look at the 2018 Chevrolet Silverado 2500HD, for example. It’s a popular truck and it’s designed to be able to work hard. The conventional or 5th wheel towing capacity is listed by Chevrolet at 9,800 pounds, compared to a Gross Vehicle Weight of 9,300 pounds if fully loaded with passengers and gear. Curb weight is just over 6,200 pounds. In other words, the truck could be towing something that weighs nearly 3,500 pounds more than it does. When things go sideways, which end of the combination is going to be in control? Probably not the truck.
This is true of every truck and SUV on the market. You need to know what your vehicle weighs (curb weight and GVWR) and how that compares to what you’re going to tow. I generally try to make sure my tow vehicle weighs more than the trailer I’m towing, but that’s not always possible and it may be necessary to employ additional items such as sway control bars to better control the load.
Trailer Hitch – There are classes of trailer hitches that are based on the weight they are rated to tow. Depending on the class of hitch, it will have a specific size receiver opening for the ball mount, typically 1 7/8, 2, or 2 5/16 inches. The class also determines how much weight can rest on the hitch when the trailer is connected. To make sure you are towing safely, there are a couple of things you need to match up here. First, make sure you are buying enough hitch for the job you want it to do, now or later. The difference in price from class to class is relatively small so it’s not worth trying to save money here if there’s a possibility you may want to tow 5,000 pounds later instead of the 3,000 you need to tow now.
Trailer hitches are typically sold separately from the electrical wiring kits needed to connect the trailer and vehicle lights together, so don’t forget to get the right kit for your vehicle.
Ball mount drop height – A trailer that is not level to the ground when hitched to the tow vehicle can produce so undesirable effects. If the trailer coupler is leaning forward, it is shifting it’s weight forward and putting more weight on the hitch than it should and may be forcing the rear suspension of the tow vehicle to squat. That reduces grip at the front wheels and changes the handling dynamics of the tow vehicle as well as it’s ability to absorb road imperfections. Conversely, a trailer that is leaning back is unloading the rear suspension and trying to lift the rear of the tow vehicle. That will cause problems as well.
To eliminate this, make sure the trailer is level to the ground while unhitched. Measure the distance from the ball coupler to the ground. Then, making sure the two vehicle is parked on level ground, measure the distance from the center of the receiver opening to the ground. The difference in height (and there is usually, but not always, at least a 2” difference in height) is the amount of drop you need in the ball mount.
Getting that right means your trailer will sit level when hitched and won’t be affecting the stance of the tow vehicle.
Brake Controller – Some vehicles that are equipped with factory tow packages come with an integrated brake controller. Others do not. The brake controller allows the driver to set the timing and intensity of trailer brake actuation. Small utility trailers typically don’t have brakes so this isn’t needed for them but trailers with a load rating over 3,000 pounds typically have electric brakes on each axle they have. Setting the brake controller correctly will prevent the tow vehicle brakes from having to stop the entire combination and can help control the trailer when necessary.
Additional Load Control Devices – For heavy loads or when the load is near or over the weight of the tow vehicle, it may be advisable to add other load control products to the vehicle. Examples of this are sway control bars or weight distributing hitches and helper springs.
Sway control bars attach to the trailer tongue and to the ball mount on the tow vehicle. They apply tension to the trailer when it wants to step out of line with the tow vehicle. This can happen due to wind gusts or the air deflecting off the front of a passing tractor trailer. The sudden rush of air will want to push the trailer sideways, but the bars should prevent or minimize that kind of movement.
Helper springs can come in two general forms. They can be an actual leaf spring that adds stability to the factory spring, providing better control or they can be an air bag that is inflated when towing and set to the pressure that provides the most stability.
As you can see, there is much more to this than just bolting on a hitch, hooking up a trailer, and hitting the road. We frequently walk customers through this discussion to help them achieve a good result that allows them to safely enjoy towing season, no matter where they’re going or what they’re bringing with them.