Most horse owners are not really interested in being truck drivers. There are some who love to debate engine size and gear ratios, but most of us just want to hook up the trailer and take our horse somewhere else to ride. Unfortunately, because our pets happen to be very large, we horse people are forced into a position of having to make decisions about heavy equipment that"normal" people never even have to think about.

There are so many different vehicles on the market that it is easy to be confused about which one to buy. Unless you know where to look, it seems impossible to find the appropriate facts even from sources that should have reliable information. However, finding the suitable tow vehicle doesn't have to be difficult once you know how to find the right numbers and then add them up.

Why is it so important to have the right tow vehicle? Towing puts extra demands on a vehicle. The engine, transmission, rear axle, and tires must work harder to handle the extra weight and drag of the trailer. The engine is required to operate at higher speeds and generates extra heat that must be diffused. The vehicle must be stable enough to support the load and keep the entire combination under control without exceeding the capacity of the engine and other components. When you are on the road, you are responsible for the safety of yourself and others. The vehicle must operate as safely with a trailer in tow as it does without it.

A common error people make is to buy the tow vehicle first and then try to find a trailer later. In fact, the best way to put your rig together is to buy the trailer first, determine how much it weighs, and then buy the tow vehicle that can handle the load. (Or at least decide upon which trailer you will buy in the future.)

The trailer you buy should fit the needs of your horse or horses that will be hauled in it. If you have small or average size horses, it isn't too difficult to find a trailer that will work for you and your horses. However, if you have horses 16 hands or over, your choices become more limited. When the horses are larger and heavier, the trailer must be bigger and stronger to be able to handle the strain of the extra load. Putting large heavy horses into a lightweight trailer is like carrying bricks in a plastic bag. The trailer will not hold up for very long. A trailer that is too small could cause extra stress to the horses, which could increase the possibility of illness or injury. And, no matter what trailer you buy, you still have to consider the weight of the horses themselves.

In order to figure out the trailer load that you will be towing you must start with the empty weight of the trailer. Usually there is a sticker on the inside of your trailer door that includes the axle capacity and the Gross Vehicle Weight Rating (GVWR). This is not the actual weight of your trailer. The GVWR is the amount specified by the manufacturer as the maximum weight that a vehicle can safely weigh when fully loaded. This figure includes the weight of the vehicle itself. Sometimes the Certificate of Origin that comes with your trailer will state the empty weight of the trailer. If so, this is usually not the weight of your specific trailer, but the weight of the standard trailer of that particular model. If you have added options or extra dimensions to the trailer, these may not be reflected on the certificate. If you are trying to downsize your towing vehicle it is very important to have the correct weight, so you may have to take the trailer to a scale and weigh it to be sure.

Don't completely rely on the dealer or manufacturer to tell you how much the trailer weighs - they may not really know themselves. You can find a scale at gravel yards, grain elevators, or commercial scales at truck stops. Do not go to a highway weigh station. To get the correct weight, you will have to disconnect the trailer from the truck while it is on the scale. (If you don't have your tow vehicle yet, you might have to ask a friend to take it there.) If you are prepared to buy a pick up truck or other large towing vehicle, you can estimate these figures or use the GVWR as the number to use. In fact, this is my recommendation.

Once you have determined the empty trailer weight (this should include the standard equipment such as mats and spare tire.) Add the weight of your horses. A weight tape can give you a number that is close enough. Add any hay, grain, equipment, tack, water, and anything else you will be hauling in the trailer and you have the Actual Weight or GVW (Gross Vehicle Weight). Another way to be absolutely sure of the GVW is to load it up with your horses and equipment before you take it to the scale

Using a trailer with a GVWR of 5000 lbs. as an example, you must make these calculations:

If this particular trailer weighs 2300 lbs., including mats, tires, and other standard equipment, and two horses being hauled in it weigh 1200 lbs. apiece, it adds up to 4700 lbs. There is a 300 lb. leeway left for tack, equipment and feed. If you put two 1500 lb. warmbloods in the same trailer (3000 lbs. of horses alone), the trailer is overloaded by 300 lbs.

It's important to understand these additional terms and definitions to simplify the selection process of the tow vehicle.

CGVWR (Combined Gross Vehicle Weight Rating)- The amount specified by the manufacturer of the tow vehicle as the maximum weight that a combination of tow vehicle and trailer can safely weigh when fully loaded.

CGVW (Combined Gross Vehicle Weight) - Actual loaded weight of a tow vehicle and trailer combination. (The CGVW must not exceed the CGVWR)

Curb Weight (or Empty Weight) - The weight of the unloaded vehicle including the standard equipment. The Curb Weight of a tow vehicle includes a full tank of gas and all fluids for operation. Curb weight of a trailer includes standard equipment (spare tire, mats, etc.)

Once you know how much your trailer weighs, you are ready to select your tow vehicle. If you are hauling a gooseneck trailer, the choice is obvious. You must have a pick up truck or a larger unit with a bed for the gooseneck hitch. However, for a tag-along trailer, there are many more types of vehicles from which to choose. Although this can be an advantage, having a larger selection available also increases the chances of making a mistake.

Every manufacturer publishes a vehicle towing guide that, as the name suggests, lists the towing capacity of each vehicle, and sometimes the manufacture includes the towing capacity under the "specifications" section of individual brochures. If you go into a dealership and ask for a towing guide, the salesmen may not even know such a publication exists. Insist upon checking capacities in writing before you make your decision. Many auto salespeople are not familiar with the specifics of towing horse trailers. If you are buying a used vehicle, you can compare specifications of new models of the same vehicle, or ask for an older guide. These ratings are also available on the Internet, but sometimes they are hard to find and you might have to do some digging though manufacturer's web sites.

Towing capacities are determined by the combination of engine size, axle ratio, and transmission. The frontal surface area of the trailer is also a consideration. It takes almost one horsepower per square foot of frontal area to move a truck and trailer at highway speeds.

The engine needs to have enough power to pull the combination not only in normal driving conditions, but also on hilly terrain, and to be able to blend and move with traffic conditions. It should also be able to perform in adverse weather conditions and, if applicable, in high altitudes.

The axle ratio is the gearing in the differential that multiplies torque. Torque is responsible for getting the load moving and providing pulling power at higher speeds. The higher the gear ratio (4.56:1, for example), the more torque. The lower the gear ratio (3.08:1, for example), the better the fuel efficiency, but the less torque. If the gear ratio is too high for the load you are hauling, you will be using more fuel than necessary, but if the ratio is too low, the vehicle will not have enough torque and will suffer excess wear and tear of the drive train. Getting just the right ratio is important for the long life of your vehicle and for the best fuel economy. If you must choose one over the other, it is better to choose the higher ratio over the lower.

The transmission provides the lower gears to start the load moving and then changes to direct drive or overdrive to reduce engine speed while the vehicle is driving at the desired speed. An automatic transmission is usually recommended because the torque converter multiplies the engine torque smoothly, making the first-gear ratio twice as effective as that of a manual transmission. In most trailering guides, you will find that the towing capacities of equally equipped vehicles will be less when the vehicle is equipped with a manual transmission. An automatic transmission is recommended for towing.

If you need a four-wheel drive for your normal driving routine without a trailer, this may be an option for you, but four-wheel drive will not increase your towing capacity if the engine and gear ratio are not adequate. Diesel engines are fuel efficient, but you must still have all the aforementioned ingredients for the vehicle to be equal to the task.

When you consult the trailering guide, keep in mind that the recommended ratings have been calculated for boat and camper trailers being towed in average driving conditions. Horses are top-heavy, shifting, live cargo that has a mind of it's own. This puts more strain on the stability of the load than hauling inanimate objects. A horse can lose its balance or throw a tantrum that can create a dangerous driving situation that is not a factor with other kinds of trailers. It's a good idea to leave a margin for driving safety and especially important if you will be driving in hilly terrain or adverse driving conditions.

For instance, if you are considering a 1500 series pickup truck and your trailer is 5000 lbs. GVW the towing guide will tell you exactly how that vehicle must be equipped to do the job. Using a GMC Sierra as an example, the 4.3L V6 engine with a 3.08 axle ratio and automatic transmission is rated to tow only 4000 lbs. In order to tow your 5000-lb. trailer with the same 1500 series truck, you must at least go to the 3.73 axle ratio to get a 5000 lb. rating. If you read the footnotes in the GMC guide, you will learn that this rating assumes that there is one passenger in the tow vehicle and the tow vehicle has all required equipment. Required equipment includes an engine cooler, transmission oil cooler, and the appropriate weight distribution hitch. If there will be more than one passenger in the vehicle, the extra weight must be deducted from the trailer weight. This is where the CGVWR comes into the equation. If the CGVWR for a vehicle is 10,500 lbs., and you deduct 5000 lbs. for the trailer, there is 5500 lbs. left for the vehicle. If the vehicle weighs 5500 lbs. with one passenger and all standard equipment the weight of extra passengers and cargo must be deducted from the trailer. (These are estimated figures being used as an example. Consult the manufacturer's Towing Guide for exact ratings.)

Towing this trailer with the V6 engine is close to the margin. So it would be better to go up to the 4.8L V8 engine with a 3.42 axle ratio which is rated to tow 6000 lbs., or the 2500 series which is rated, depending upon equipment, from 6500 lbs. to 10,500 lbs.

Many people who are only hauling one or two horses want to tow the horse trailer with the family vehicle. The popularity of sport utility vehicles and smaller trucks has fueled the fire. If you are hauling a two-horse trailer with one or two average size or small horses, it's possible to tow with a smaller vehicle, but you must be very careful that the tow vehicle is properly rated to pull the trailer. It's especially important that it's equipped with towing package, weight distribution hitch, and operative brake system. Also, paying strict attention to the CGVWR is vital with these lighter vehicles because it is so easy to overload the combination.

If you are hauling a two-horse trailer with large horses and/or a dressing room, downsizing to a sport utility vehicle may not be the best option for you. There are many other vehicles on the market that are not pick up trucks, but have a higher towing capacity and a longer wheel base which adds stability.

A gooseneck horse trailer is recommended for a trailer for three horses or more, so a pick up truck is the only choice. The same formula applies to choosing the correct model - add up the numbers and consult the towing guide. The ratings for hauling a gooseneck, which is considered a semi-trailer, will probably be higher than hauling a tag-along trailer. For instance, truck that is rated to tow a 10,000-lb. trailer may be able to haul as much as 18,000 lbs. if the trailer is a gooseneck.

In recent years, manufacturers have been building trucks higher off the ground, especially four wheel drive models. If you choose one of these trucks, you may need to have your trailer custom tailored to clear the truck bed even if it is equipped with an adjustable gooseneck coupler. The trailer manufacturer can "block" the axles to raise the trailer, but if you do this, realize that any ramps on the trailer will be steeper than originally intended. Another option is to have the truck lowered. Some truck manufactures will do this at no cost and others will charge you for the option.

If you are buying a used vehicle, all the same rules apply. It goes without saying that your tow vehicle should be in the best running condition possible. You don't want to break down on the road with your horses in tow. If you are uncertain about the engine and axle ratio take it to a mechanic to have it checked over.

Now that you know how to add the numbers, you can see that it isn't so difficult to choose the tow vehicle that will give you peace of mind when you take your horse out for a ride.  

About the authors:

Neva Kittrell Scheve, along with her husband Tom, 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. Besides being authors, clinicians, and writers of numerous published articles on horse trailer safety, both Tom and Neva have designed and developed the EquiSpirit and EquiBreeze line of horse trailers in Southern Pines, NC. For more info, contact Tom: 1-877-575-1771, tom@equispirit.com or visit them on line at equispirit.com.