How do I know what size trailer will best fit my horse?

By Tom and Neva Scheve
Two horse straight load.

An inside width of 6' (a trailer quoted as having a 6' width may vary by a few inches) with a height of 7' (square sided roof rather than rounded), and a total stall length of 10', will fit a horse from about 14 hands up to about 16 hands. Add 2" to the roof (7'6"), and the horse can be up to 16-3 hands. From 16-3 hands up to 17 hands, you should add another 2" (7'8") to the height, and 6" to the length from butt to breast and 6" to head area (11' total stall), or just add 1' to the head area depending on the "butt to breast" size of your horse.

If you're roads are not to narrow, you can also go to a wider axle, and have an inside width of approximately 6'8" (102" axles) with no wheel wells inside the trailer. For horses up to 18 plus hands, the trailer should have the 6'8" width, 7'8" height, and 11' total stall length. For horses, such as draft horses, that are approaching 19 hands with weights approaching 2000 lbs., the trailer should be close to 8' tall with 12' total stall length, with extra floor supports, upgraded axles and tires.

At EquiSpirit, we have three size options available on all are models (straight loads):

Be careful if a trailer company does not have various model sizes in their lineup, but is just adding footage and width without upgrading tires, floor structure, axle rating, and re-engineering the balance of the trailer.

Regarding slant loads:

Most slant loads will not fit horses over 15-3 hands comfortably. Most slant loads that quote 10 to 11 feet on the diagonal (far corner to far corner) will, in reality, will have stall lengths that are only be 8 to 8 ½ feet long (measure down the center). Some slant loads purport that they have warm blood size stalls, but the only way a slant load can fit larger horses (since there are legal limits to how wide a trailer can be, and there are wheel wells in all stalls up to 4 horses) is to widen the stall, or take out a divider. When this is done, a horse can stand more front to back. The smaller the horse, the better it will fit in a slant load trailer. It's our opinion that the only positive trait to a slant load is that you can stack more horses in a shorter trailer.

Is a ramp better? Or a step-up?

A well designed, easy to lift, low angled ramp with springs across the bottom of the ramp (not on the sides) is better than a step up, especially on all two horse straight load trailers. Without a ramp, there is always the danger of a horse backing out, stepping down, and sliding under the back of the trailer. A hot day, a bee in the trailer, etc., can cause even the best trained horse to want to scramble out quickly. A ramp eliminates the possibility of a horse sliding under the trailer from ever happening. (Note: don't let some dealer tell you that a horse can slide under the side of a ramp or step off the side and get seriously hurt).

Should I tie my horse's head or leave him loose?

We feel that the best stall situation is one in which the horses are traveling straight, head forward, no lower center divider, no back post, and the horses head is tied with enough rope to let him stretch his neck, especially if he is eating hay in the trailer. He will need to be able to cough out any hay that might get into his respiratory system. A quick release snap is important, but not one that will release on its own. We have designed and developed a special lead rope that is adjustable in a way that a horse can't get caught in it, and will quick release on both ends.

Is the slant-load style the best? Why or why not?

It's our opinion that the only advantage to a slant load is exactly the same reason why they were first developed. One can stack more horses in a shorter trailer. Although many articles have been written since then that have tried to support that slant loads provide a better ride for horses, none that we have found, have been accurate.

The negatives to slant loads are numerous. If a front horse has a problem, you can't reach it without unloading the other horses (unless you have a front unload ramp). Tow vehicles are always moving forward even when they make turns. During all that stopping and starting, a horse needs to plant its front and back feet for balance, rather than standing on an angle where its constantly falling on its front forward leg, and rear hind leg. The stall length is rarely big enough unless your horses are very small. Most horses that are 16 hands plus will have their noses pushed up against the road side wall, and their butts squeezed against the ditch side wall. The size problem comes from the limitation of what the legal width of a trailer can be. It can go up to 8'6" but the wheel wells are then inside the trailer and are still restricting the horse's space.

How much ventilation does a horse really need? Summer? Winter?

In the summer, horses need as much ventilation as you can give them. This can be provided by having large windows on the sides of the trailer, in the rear doors, and near the horse's heads. Also, there should be at least one roof vent for each horse. On tag-alongs, a bulkhead window with front opening windows in the nose of the trailer can provide additional ventilation. Oscillation fans that run off you tow vehicle battery (the same as your interior lights) can provide additional ventilation if you get stopped in traffic. Screens are important because they allow the air in without letting in insects, wasps, cigarettes, and road debris.

In the cooler months, it's nice to have an dual wall, insulated trailer that will hold in the horses body heat. But it is still wise to crack windows, and adjust vents (dual scoop vent) to allow the air to flow freely through the trailer.

Where do the vents do the most good? Above their heads.

Should I bed my horse when hauling? If so, with what? Straw? Wood shavings? What is best?

Using or not usiing bedding, depends on your horse. Some geldings don't like to "splash" themselves in the trailer. A coating of shavings, or hay, can solve this. Otherwise, it is not necessary. However, we have found that shavings left in a trailer can draw moisture and cause the inside of the trailer to "sweat".

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