by Mark J. Polk
originally printed in PopUp Times Magazine
“Yaw,” more commonly known as “sway” in the RV industry, is a bad word for pop up campers. The definition of yaw or sway is a side-to-side movement. Nothing will ruin the way you feel about camping faster than the first time you experience trailer sway.
You go to your local dealership and find a pop up with the perfect floor plan for you and your family. The sales person knows that it will be close to the maximum weight that your tow vehicle can pull. He really needs a sale because things have been slow. Rather than risk losing the sale, he decides not to explain the added expense of the proper hitch work to safely tow your new trailer.
You’re all packed up for a weekend getaway. You made all of your pre trip checks and you’re ready to go. You load the most precious cargo you have, your family, into your tow vehicle and head out on a new venture. Everything is fine when you leave the house. You take the on-ramp to the interstate. You’re cruising at the speed limit, enjoying the music on the radio. Suddenly, out of nowhere, a transfer truck going twenty miles over the speed limit is passing you as if you’re sitting still. The pop up is pulled into the draft created by the truck. In an attempt to correct this totally unexpected event, you over-steer, and the trailer begins to go in the opposite direction. Not really sure what to do, you turn the steering wheel to the left, then to the right. Now the one-ton trailer behind your sport utility vehicle is veering sharply from side to side and begins to affect what little control you have over the vehicle. The results are catastrophic…
Okay, since this is a magazine article, let’s start over and fix this before you even realize that there is a potential problem. You purchased your pop up from a responsible local dealership. At the risk of losing the sale, your salesperson explains that you will require some specialized hitch work to pull your new trailer safely. You are a bit skeptical, feeling like he just wants more of your money. (Besides, your father never needed any of this stuff. He just hooked his trailers onto a ball on the bumper.)
You decide to give the salesperson the benefit of doubt and listen for a minute. He shows you in his book that your tow vehicle is rated to tow a maximum of 3,500 pounds. Then he explains what you must factor into that tow rating. It includes the weight of your new camper, any after market add-ons, like the roof-mounted air conditioner that the dealership is going to install, all of the cargo that you load in the trailer and in the tow vehicle, and the weight of the people in the vehicle. Now all of the sudden the sales person has your undivided attention. You had no idea that all of this had to be considered. Now he shows you the weight label on your new trailer. The unloaded vehicle weight (UVW) is 2,100 lbs. The air conditioner weighs 100 lbs. To be safe, he estimates that you will carry about 300 lbs. Of cargo, and then adds 400 lbs. (for you, your wife and the children).
You are amazed how fast things add up. Now you have 2,900 lbs. instead of the 2000 lbs. that you thought it was. It isn’t over yet. Your sales person starts to explain that every state has different requirements on how much a trailer can weigh before it requires trailer brakes. In your state, the weight is 3,000 lbs., but as a responsible dealership, any trailer they order that weighs over 2,000 lbs., they have brakes installed by the manufacturer. He explains that even though your vehicle is rated to tow 3,5000 pounds, the brakes on the vehicle were designed to safely stop the vehicle’s weight, not an additional ton and a half being pulled behind it.
He takes you to the parts department and shows you a brake controller and explains that this is what activates the trailer brakes, and the dealership can install it when they do the wiring for the trailer lights. You like the features he explained about the brake controller. The fact that you can manually adjust the amount of braking action, so that when you hit the brake pedal, the tow vehicle and the trailer work together to stop the weight in a reasonable amount of time. What you really like is the part he explained about the slide lever that activates the trailer brakes without using the vehicle brakes. He said if you’re on a steep grade and you don’t want to prematurely wear out the vehicle brakes, you slowly slide the lever and the trailer brakes will slow you down. But what really sold you on it was when he explained that if the trailer starts to sway, you could gently tap the lever activating the trailer brakes on and off to help straighten the trailer out.
He then went on to explain that trailer sway is one of the biggest problems you will encounter while towing the pop up. He took the time to explain that for the trailer to pull properly, the manufacturer recommends that the tongue weight resting on the ball mount should be 10 to 15% of the total trailer weight. If it is more than 15%, they have what is called a “weight distribution hitch” that takes the additional tongue weight and distributes it to the axles on the tow vehicle and the trailer where it should be. If it is less than 10% when you load your cargo, you distribute it to add some additional weight on the tongue. He looked up the pop up you were buying in the brochure, and the tongue weight was 305 pounds. With the air conditioner installed and cargo loaded, it would be between the 10 and 15% range. He said that a weight distribution hitch was more commonly used with heavier trailers, and in some cases with pop ups, depending on the tow vehicle. In this case, however, it would not be required.
The next thing he asked was if the vehicle had a receiver. He explained that the part of the hitch that is bolted to the vehicle is called a receiver, and he showed you a chart that had several different classes of receivers, depending on the amount of weight you will be towing. The class II receiver was rated for 3,500 lb. gross trailer weight and 300 lb. maximum tongue weight. For a small difference in price, he recommended a class III receiver rated for 5,000 lb. gross trailer weight and 500 maximum tongue weight (since the trailer tongue weight exceeded 300 lbs.).
With that done, he said he would show you a component that the dealership strongly recommends to anyone purchasing a pop up. He walked over and picked up a part from the shelf called a “friction sway control.” One end of it is mounted to the hitch in the receiver and the other end to the tongue on the camper. You adjust the amount of friction by turning the lever clockwise for more friction and counter clockwise for less friction. He explained that you turn it in 1/8” increments until you get it adjusted where you feel comfortable. This will not totally eliminate sway, but it will control it to the point that you feel in control of the vehicle when you’re pulling your camper.
Finally, he said that would do it. For less than 10% of the price of the pop up, you can get all of the hitch work done and ensure that your family is safe when you go on a trip. At this point, you are convinced that the salesperson has your best interest in mind and is not just trying to make more money for the dealership.
Now you are all packed up for your first weekend getaway with your new pop up. You made all of the pre-trip checks that the dealership explained, and you are ready to go. The family is loaded into the vehicle and you back out of the driveway. You take the on ramp to the interstate and settle in, enjoying the music on the radio. Suddenly, out of nowhere, a transfer truck going twenty miles over the speed limit passes you as if you were sitting still. You feel a slight movement behind you– just enough to remind you that you’re pulling the pop up. You look at your watch and tell the family that you should be there in a couple of hours.
Mark Polk is the owner and operator of RV Education 101, a video production and educational seminar company specializing in the RV industry. For more information visit www.rveducation101.com or call 910-484-7615