Mark J. Polk, RV Education 101
How to safely and properly tow a trailer involves many factors. The tow vehicle and trailer must be properly matched and you need all the correct hitch components. Also, you need a thorough understanding of topics like tires, weights, hitching and unhitching and actually towing the trailer down the road. Today I want to look at five trailer towing mistakes RV owners make to prevent any from happening to you.
Number one and possibly the most important mistake is not properly matching the tow vehicle and trailer. The first step is to determine exactly how much weight the tow vehicle can safely tow. Vehicle tow capacities are in the vehicle’s owner manual, and there are published towing guides available on the internet. You need to know how your vehicle is configured when you use a towing guide and pay attention to any footnotes.
After establishing the vehicle’s towing capacity make sure the trailer you plan to purchase is compatible with the tow vehicle. This is where you can get into trouble. Lots of people look at the trailer’s dry or Unloaded Vehicle Weight (UVW) and assume they can tow the trailer. When you load camping supplies and account for water, propane, and dealer-installed equipment, the tow vehicle might be overloaded. Try to find a trailer with a Gross Vehicle Weight Rating (GVWR) equal to, or less than, the tow rating of your tow vehicle. There is typically a substantial difference between the dry weight and the GVWR. The trailer can be loaded to the maximum GVWR, and the tow vehicle is still rated to tow the trailer.
Next, and this is another weight issue, lots of folks don’t consider any weight added to the tow vehicle itself. The vehicle manufacturer bases tow ratings on an empty truck with full fluid levels, and a driver weighing 150 pounds. As an example, let’s use a tow vehicle rated to tow 5,000 pounds. Add three passengers for a combined weight of 400 pounds, 150 pounds of cargo in the bed of the truck, 100 pounds of aftermarket products added to the vehicle, for a total of 650 pounds. This reduces your 5,000-pound tow capacity to 4,350 pounds. Any weight you add to the tow vehicle reduces the towing capacity by that same amount. So you can see how easy it is to get into trouble with weights.
Number three on my list is trailer tires. Trailer tire blowouts are commonly blamed on faulty tires when the actual causes are old tires, overloaded tires, or under-inflated tires. When I say old tires I mean tires damaged by the elements, usually sun-related damage. If the trailer is stored outdoors, cover the tires to prevent exposure to direct sunlight. Periodically inspect the tire sidewalls for any cracking or checking. Never tow a trailer with any of these tire conditions.
Trailer tire weight ratings are based on the amount of air pressure in the tire. You should familiarize yourself with tire load and inflation tables that tire manufacturers publish. After you are familiar with these tables you need to have the fully loaded trailer weighed to see if any overload conditions exist.
For accurate tire information, you need to weigh each wheel position individually. Some RV rallies and other organized events offer a weighing service to weigh by individual wheel position. The next best thing is to weigh each axle separately and then together. When you weigh by axles you’ll know if the trailer is within the axle weight ratings, but you won’t know how that weight is distributed side-to-side. At a minimum, it gives you a better idea of tire inflation based on axle weights.
Number four is not using the proper hitch-work. It’s important to understand that every component in a towing system has a weight rating. The towing system is based on the weakest link in the chain. For example, if the vehicle is rated to tow 6,000 pounds and the hitch ball is rated for 5,000 pounds, the most you can tow is 5,000 pounds. The hitch receiver, hitch ball, ball mount, safety chains and every component in the towing system have individual weight ratings.
Next, make sure the trailer tongue weight is 10 to 15 percent of the loaded trailer weight for trailers weighing more than 2,000 pounds. Too much or too little tongue weight can have adverse effects on how the trailer tows. Your vehicle owner’s manual specifies when you need a Weight Distribution Hitch (WDH) based on trailer tongue weight. A WD hitch uses additional hardware to distribute a percentage of the travel trailer’s tongue weight to the axles on the tow vehicle and the axles on the trailer. Weight distributing hitches are used to tow heavier trailers, and to improve the tow vehicle’s handling characteristics. If the trailer you are towing has brakes, you need an electronic brake controller to activate the brakes. I recommend you use some type of sway control on any trailer that weighs in excess of 2,000 pounds.
Number five on my list is not performing pre-trip checks prior to pulling the trailer. Lots of preventable towing-related incidents happen because a person didn’t complete pre-trip checks. Checklists help make sure nothing was forgotten or overlooked on the trailer or the tow vehicle prior to leaving on a trip.