Shipping is a fact of life for almost every horse. Even if you don't compete, trailering to parks and the veterinary hospital are common trips. If you prepare your horse and trailer properly ahead of time, your outing will be safe and stress-free. This will not only ensure the safety of your horses but also prolong the life of the trailer.
Appropriate Tow Vehicle
The longer the wheelbase on your car or truck, the safer the towing setup. The longer vehicle (such as a full-size pick-up truck or Suburban) will be less influenced by the weight behind it, and will be easier to steer and drive straight. Automatic transmissions also provide a smoother ride, and that engine must be big. The vehicle must have heavy-duty shock absorbers in the rear to "take" the extra weight behind while still riding level. The cooling system must also be powerful enough to prevent engine overheating in the summer. Don't ever run the air-conditioning when you are towing – it stresses the engine too much. Large mirrors on both sides are a must for safe visibility as the rearview mirror just shows that the trailer is still following you.
Use the appropriate size hitch ball on your truck to fit the "opening" in the trailer's tongue. The height of the hitch ball should be such that when the trailer is attached to the vehicle, the trailer rides level. When a hitched trailer is "uphill" in front, the horses have an awkward, stressful ride and a lot of strain is placed on the hitch/tongue (possibly causing it to crack and break over time). Safety chains should be strong and of the proper length. A small wire should be present and attached so that in an accident it will activate battery power to lock the trailer brakes. A weight-distributing hitch with bars from the hitch base to the sides of the trailer tongue will improve stability and safety during towing. Your trailer dealer can install this type of hitch on your rig and determine the optimal tension adjustment for the bars.
Comfort is Key
Make sure the trailer is big enough for the horse. If the roof is too low or the stall is too short or narrow, your horse will be nervous, uncomfortable and unsteady. The horse must be able to spread his legs as necessary to remain balanced.
Open all of the windows and vents for travel (except for windows in the front wall). Cool, fresh air during transport is very important in preventing respiratory disease/infections caused by shipping. Most horses appreciate a full hay net to munch on during the trip. Just make sure that your horse can get his head away from the hay if he wants to and that hay chaff won't be blowing in his face.