Does your trailer have a bad attitude? The term attitude can be defined as the angle of a vehicle in relation to its direction of movement. In other words, if your trailer has a bad attitude, it’s not level.
If your trailer isn’t level, your horse has to work that much harder to keep his balance, which increases stress on his joints and muscles.
Here, we’ll first explain how trailer weight, axles, and tires can affect your trailer’s balance. Then we’ll give you six ways you can adjust your trailer’s attitude, if necessary.
Gross Vehicle Weight
Your trailer needs to be level so that your loaded trailer weight is distributed equally to all four tires and both axles. To more fully understand what this means, here are definitions of Gross Vehicle Weights (GVW) and Gross Vehicle Weight Ratings (GVWR).
The GVW is the loaded weight of your trailer including the trailer, horses, tack, and equipment. The GVWR is the maximum weight the trailer can weigh and still be safe, which is determined by the manufacturer. The GVWR is determined by how much weight the axles and tires can hold.
Note that some manufacturers will add the tongue weight to the GVWR. For example, if a tag-along (bumper-pull) trailer has two 3,000-pound axles, and a tongue weight of 450 pounds (as supported by the tow vehicle), the GVWR could be stated as 7,450 pounds.
The coupler is also rated on tag-alongs. If the coupler rating is less than the axle ratings, then the GVWR must be reduced to the rating of the coupler.
The GVWR will always be the lowest rating of all the components, just like the weakest link on a chain.
Weight Rating: Axles
The axle’s weight rating reflects its weight-bearing capacity. The manufacturer will choose axles with capacities that will best fit the trailer’s projected loaded weight. The manufacturer won’t use an axle with a rating lower than the determined weight of the loaded trailer.
Too much of a good thing isn’t desirable, because an overrated axle will give your horse a stiff ride. Once the manufacturer determines the axle size, the rating will be placed on a sticker located somewhere on the trailer.
If a trailer has, say, two 3,000-pound axles, the GVWR will be 7,000 pounds. Many trailer owners is interpret this rating, thinking it’s the actual weight of the trailer.
For example, let’s say the weight of an empty, two-horse, tag-along trailer with dressing-room is 3,400 pounds. Add two horses and tack, and the weight is 5,500 to 6,500 pounds. This would be the GVW.
If your trailer isn’t level on the axles, depending on whether it’s higher or lower in front, it’ll unevenly distribute the weight to one or the other axle, causing it to become overloaded.
As a result, your trailer will track unevenly, probably sway, and may even experience a bend or break in the overloaded axle. This imbalance will also overload the tires.
Weight Rating: Tires
The same principle relates to the tires, which also have a weight rating. This rating is etched right on the tire, along with the maximum tire pressure.
The combined rating of all four tires must add up to match or exceed the GVWR of the axles.
If we take the same two-horse trailer mentioned earlier, the manufacturer will install tires rated at least 1,820 pounds (or a bit higher) each, so that the total capacity of all four will equal 7,000 to 8,000 pounds.
If the trailer isn’t level, it’ll put more weight on the front or the rear tires. As a result, the tires will be stressed beyond capacity and can blow.
6 Attitude Adjustments
Here are six ways to adjust your trailer’s attitude, to make sure it’s being equally supported by both axles and all four tires.
1. Check tire pressure. Check the tire pressure on all four tires to make sure they’re equal. Find out the tire’s maximum pounds per square inch (PSI). This figure is stamped into each tire in small print. Then fill the tires to this maximum pressure when they’re cold. The tires will flex less and run cooler while you’re on the road if they’re filled to their maximum PSI.
2. Find level ground. Hook your trailer to your tow vehicle, and drive the entire rig onto a flat, level surface, preferably concrete or blacktop. Stand on the side of your trailer, and see whether it looks level.
Then eyeball the tires to see whether they’re equally flat where they touch the ground. If one tire is more rounded, there’s less weight on that tire, which indicates an uneven trailer.
Most likely, your trailer won’t be perfectly level, but close. If you can’t make your the trailer perfectly level, it’s better to have it slightly higher in the front, as it’ll track better.
3. Adjust the hitch ball. If your trailer isn’t level, determine the amount the front end is up or down, then raise or lower the hitch ball accordingly. If you have an adjustable coupler, use this to make adjustments.
4. Buy a ball mount. If you have a tagalong with a standard ball mount and ball that slides into your frame-mounted receiver hitch (never use a ball on a bumper), you can purchase a ball mount that has various drops to achieve the desired height. These drops usually come in two-, four-, and six-inch sizes.
If the back of your tow vehicle sits extra low and the ball mount needs to be taller, remove the ball, and place the ball mount upside down into the receiver hitch, then refasten the ball to get the desired height.
Find a professional to torque the ball and nut onto the ball mount. If you use a weight-distribution system, the ball is usually adjustable, and can be raised and lowered on the existing ball mount. Make sure the weight-distribution bars are attached correctly, because they do raise the trailer a bit when hooked into place.
5. Check the gooseneck’s coupler. Most gooseneck trailers have an adjustable coupler that allows you to fine-tune the trailer up or down to level it. However, this doesn’t necessarily mean it can be leveled to fit over your truck’s bed.
Many older gooseneck trailers don’t have a tall enough nose to provide adequate height over the bed of many of today’s tall, four-wheel-drive trucks and still be level. An adjustable coupler will only raise the front part of the nose; it won’t raise the entire gooseneck over your truck’s bed.
If the entire gooseneck doesn’t adequately clear the bed, it’ll hit the tailgate when you drive over uneven ground. Check this clearance before you buy.
6. Adjust the gooseneck’s coupler. To level a gooseneck to your tow vehicle, park your unhitched trailer on a flat surface, and level it without the vehicle attached. Then lower the truck’s tailgate, and slowly back under it.
Make sure there’s at least eight inches of clearance between the top of the truck bed’s sides and the bottom of the trailer’s gooseneck portion. Then adjust the coupler to keep your trailer level.
Tom Scheve and Neva Kittrell Scheve (877/575-1771; www.equispirit.com) are the authors of the nationally recognized textbook, The Complete Guide to Buying, Maintaining, and Servicing a Horse Trailer. Neva also has two other horse trailer books to her credit, including Equine Emergencies On The Road with Jim Hamilton, DVM.
The Scheves present clinics at equine expos and promote trailer safety through articles in national magazines. They’ve designed and developed the EquiSpirit, EquiBreeze, and ThoroSport lines of trailers.