If you have a truck, chances are at some point you’re going to want to tow something. Even before you make a purchase, it’s a good idea to know about things like towing and hauling capacity, and to have a good understanding of what tongue weight, gross trailer weight, and other specifications mean.
This also affects the hitch you install as well. Will a Class III hitch do the job, or do you need a Class IV or even Class V? It depends. There are a number of factors that go into what your truck can tow and what kind of hitch you’ll need.
First, let’s define terms when it comes to trailers, hitches, and trucks. While manufacturers used to do their own tow testing, and consumers just had to take their word for it, now most have adopted the SAE standards referred to as J2807.
There are two kinds of towing. One is conventional towing with a ball and a hitch. The other is weight balanced towing which is done with a fifth wheel hitch or a gooseneck hitch. Often when you look at the towing capacity of a truck, if it’s listed as J2807 compliant, it’s been tested with weight distributing hitches.
Tongue weight (TW) is the amount of weight carried on the tongue of the trailer. The Gross Trailer Weight (GTW) is the weight of the trailer fully loaded. For instance, in the case of an RV, this would mean that both water tanks are full.
Towing Capacity (TC) is the maximum weight the truck can carry. Many owner’s manuals will tell you the exact numbers for conventional towing as well as the towing capacity mentioned above. They’ll also give you tongue weights, but these are seldom mentioned in sales materials.
What’s behind the numbers? Well, there are a couple of factors that go into the actual towing capacity of a vehicle. The first is the gross weight of the vehicle fully loaded itself. This means with the maximum number of passengers at a weight of 150 lbs. each and a full tank of gas. Remember there’s a difference between gross vehicle weight and the weight totally loaded.
Second, your truck suspension is designed to hold a certain amount of weight in the rear. This is normally hauling capacity, and it assumes a balanced load. The reason tongue weight is much lower than this is that weight is on the very rear of the vehicle and depends upon a hitch attached to the frame (more on that in a moment). If a trailer is within the towing capacity of the truck and is well balanced, this usually isn’t a problem. The average light-duty truck can carry between 500-700 lbs. TW, but some of the GM heavy-duty trucks can carry even more, up to 1,300 lbs. Generally, TW is about 10% of the overall conventional towing capacity.
For most light-duty trucks, this conventional towing capacity follows the math over 5,000-7,000 lbs., and up to 13,000 lbs. for the GM Heavy Duty trucks (GMC and Chevy).
This capacity is also affected by your tires. Stock tires are designed to handle this tongue weight and the specified towing capacity. Exceeding that weight or putting inferior tires on your truck can result in disastrous tire failure when towing leading to serious harm and injury. The point is that today’s towing capacities are well tested and exceeding them can make you personally liable for an accident that might occur.
Conventional hitches with a ball come in several classes from Class I-V. The difference is in towing capacity. The general rule of thumb is to install a hitch that matches your vehicle towing capacity.
For the most part, Class I and II hitches are for passenger cars or light-duty vehicles and are more often used for bike racks, cargo boxes, or extremely light loads like a jet ski or motorcycle. They can be used to pull small trailers like those rented by U-Haul and even an ATV or small boat. For most truck applications, this is too light of a hitch, and not recommended
For most truck applications, even light trucks, a Class III hitch is recommended. These hitches are designed to tow up to 8,000 lbs. and can handle tongue weights of around 800 lbs. This will cover all but the heaviest duty trucks out there, at least for conventional towing.
Add a fifth wheel hitch or gooseneck hitch though, and you can increase towing capacity by up to 50%. For example, the Ford F-250 that can tow 7,000 lbs. conventionally can tow 10,500 lbs. with a weight distribution hitch of similar capacity.
Many class IV and V hitches fall into this category. There are some conventional hitches in this category though, designed for those heavy-duty trucks that have the towing capacity to handle heavier trailers and tongue weights. Most trailers of that weight class though, like horse trailers and large RV trailers come with a fifth wheel connection.
The most important thing is passenger and vehicle safety. This is why towing capacity limits are so important to observe. From braking systems to tires and suspension, trucks are designed to haul certain loads and no more. Overload them, and you could be liable for any damage that occurs, and your insurance will most likely refuse to pay.
When it comes to trailers and hitch capacities, know what you’re getting into when you purchase both the vehicle and the trailer, and be safe!