The Danger of an Un-Level Trailer

Why should a trailer be level? For a horse trailer to avoid overloading one of the four tires or possibly breaking one of the axles, it must be level when hitched to a tow vehicle. What we mean by “being level” is that the weight of the trailer should be sitting evenly on both axles and all four tires. Since each tire and axle is rated to sustain up to a specific maximum weight, any weight over that specific weight will overload the tire and result in a blow-out or a broken axle. With most horse trailers today being equipped with rubber torsion axles, weight shifts from one axle to another rather quickly when raising or lowering the nose, making it even more critical to insure that the trailer is level.

Leveling a horse trailer.

Preparation: Check each tire’s pressure to ensure that they are all the same. This is important to achieve a correct level. I suggest filling them to the maximum pounds per square inch (psi) – they will flex less, ride cooler, and less apt to blow. You can locate the psi of the tires on the side wall.

Adjustable Bumper Pull CoulplerBumper Pull Trailers: To correctly set the level of your bumper pull trailer, park the trailer and tow vehicle on a flat surface. If the trailer is blatantly un-level when hooked to the tow vehicle, unhitch the trailer and raise or lower it so that the trailer is level. Since fenders, running boards, and other flat spots on the trailer may not be straight, using a level on one of these areas may not give you accurate information.

The best way to determine the trailer’s levelness is to first, stand a distance from the trailer and observe by sight if it looks as if it is sitting level. Then look at the tires to determine if they are equally flat rather than one tire being rounded. The rounded tire means there is little or no weight on it. The next step is to determine how to achieve the correct trailer height when the trailer is hitched to the tow vehicle. This can be achieve in two ways. EquiSpirit has an adjustable coupler on all its bumper pulls so with a wrench, you can adjust the trailer coupler up or down to the height of the ball mount on the tow vehicle. Most other bumper pull trailers do not have this feature, so you will need to choose a ball mount with the right height to keep the trailer level when hitched up. Ball mounts will have what is called “drops” (0”, 2”, 4” 6”) so depending on the height of your tow vehicle, you will need acquire the proper ball mount. You may not get the level exact, but close is okay as long as there is flatness on both tires. If the level is slightly off, have the nose a bit up rather than a bit down – it will track better.

Adjustable Gooseneck CoulplerGooseneck Trailers: The gooseneck trailer should be unhitched from the tow vehicle and parked on a flat, level surface. Observe the trailer to see if it looks level and to determine that the tires ( tires need to have the correct psi) are equally flat on the bottom rather than one being more rounded and the other more flat.

Once you determine that the trailer is level, measure from the ground to the lowest part of the gooseneck. Then measure from the ground to the top of the tailgate or side of the bed of your truck. Substract that distance from the distance from the ground to the top of the gooseneck. The amount will be the clearance you will have from the top of the tail gate to the bottom of the gooseneck with the trailer sitting level. It should be at least six inches – preferrably seven or eight so that the trailer does not hit the tail gate or sides of the truck when going over uneven terrain. If you prefer not to pre measure, with the trailer sitting level, drive your truck under the gooseneck (make sure your tailgate is down). If the clearance from the bottom of the gooseneck to the top of the tailgate and sides of the truck is under six inches, there will not be enough clearance to safely pull the trailer. The gooseneck will most likely hit the tailgate or the sides of the truck bed, especially on uneven terrain. If your tow vehicle adequately clears the truck bed while the trailer is sitting level, you can adjust the coupler up or down to meet the ball while the trailer remains level.

Note: Most all gooseneck couplers are adjustable by loosening or removing a couple bolts and sliding the coupler up or down. It’s important to note that the adjustable coupler does not raise the whole trailer up and down, just the nose. So if the clearance from the top your tailgate (and sides of your bed) to the bottom of the gooseneck is less than 6” while the trailer is sitting level, raising the coupler will only raise the nose of the trailer, shifting weight onto the rear axles and tires. The adjustable coupler’s purpose is to adjust for different height truck beds such as a four wheel drive as opposed to two. If your trailer does not have the proper clearance over the truck bed, your options are limited. You can purchase a trailer that will fit your current truck, purchase a truck that has a lower truck bed (two wheel drive as opposed to four), or you can have the axles blocked up 4” by your local service center.

This horse trailer safety article is provided by EquiSpirit Horse Trailers.
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