Properly Matching a Tow Vehicle and Trailer
[maghub_sidebar]
How To Tow Anything! typography
A large SUV like the Ford Expedition is a great match for a travel trailer. However, since full-size SUVs can seat up to seven passengers plus cargo (as well as the potential for additional cargo on a roof rack) it’s particularly important to pay attention to the vehicle’s tow rating, payload rating and GAWR, as well as the gross trailer weight and hitch weight of any trailer you are considering.
Ford Expedition with a travel trailer
A large SUV like the Ford Expedition is a great match for a travel trailer. However, since full-size SUVs can seat up to seven passengers plus cargo (as well as the potential for additional cargo on a roof rack) it’s particularly important to pay attention to the vehicle’s tow rating, payload rating and GAWR, as well as the gross trailer weight and hitch weight of any trailer you are considering.
How To Tow Anything! typography
Properly Matching a Tow Vehicle and Trailer
How to find a vehicle’s tow and payload ratings and understand the towable alphabet, from CCC to GAWR, GVWR and UVW
By Chris Hemer / Photos by author and Chris Doughtery
T

railers are by far the most popular RV choice, simply because many people already own half of the equation: the tow vehicle. However, that doesn’t mean that creating the perfect tow vehicle/trailer match is easy; balancing your needs and wants with what a vehicle is engineered to tow can often be a challenge, particularly when the whole family is taken into consideration. However, once you have the correct information in hand, narrowing down your best choices will make it easier for you to find the right trailer, tow vehicle or both.

Know Before You Tow
Let’s begin with the beginning. If you’ve already got a truck or SUV and you’d like to find a trailer that’s a good match, the first step is to determine your vehicle’s tow rating (if you don’t know it already). Most vehicles designed for towing list this information in the owner’s manual under “towing” or “trailer towing,” and the rating may vary depending on how the vehicle is equipped. Factors that may influence the tow rating include the engine, transmission, drive system (RWD/FWD or 4WD/AWD), the final drive ratio and whether or not it was ordered with a towing/payload package.

Owner’s manuals for most popular brands built in the last 10 years or so are also available for free online — simply enter the make and model of the vehicle in your favorite search engine, followed by “owner’s manual.” Most of the time, this will lead you to an owner’s site, for example, https://my.chevrolet.com/how-to-support or https://www.mopar.com/en-us/my-garage/select-vehicle.html. If you own a Ford product, you’re in luck — Ford publishes comprehensive towing guides going all the way back to 2004: https://www.fleet.ford.com/towing-guides/. Honda, Hyundai, Nissan and Toyota also have sites that will let you download owner’s manuals.

If you can’t find the tow rating in the owner’s manual, a dealership service department should be able to help you find out how the vehicle is equipped by looking up the Vehicle Identification Number (VIN). A word of caution here: Don’t rely on one of the tow rating calculators or formulas that you may find online, because these typically only display the highest available tow rating for a given model and don’t break down tow ratings based on your vehicle’s specific equipment.

The other consideration is the tow vehicle’s payload rating, which is calculated by subtracting the vehicle curb weight from its gross vehicle weight rating, or GVWR. Contrary to popular belief, the payload isn’t just how much stuff you can carry — it’s the maximum allowable weight for both cargo and passengers. This is important information that can also affect what the vehicle will be able to tow. The payload capacity of the vehicle can be found on a “Tire and Loading” information decal inside the doorjamb or edge of the driver’s door, or in the vehicle owner’s manual.

label that points out the gross vehicle weight rating and gross axle weight ratings
All vehicles, even passenger cars not intended for towing, must have a label inside the driver’s side door that points out the gross vehicle weight rating (GVWR) and gross axle weight ratings (GAWR) front and rear. Note that tire and inflation pressure are part and parcel to the GAWR; this Ford truck has a front GAWR of 4,800 pounds when equipped with LT275/70R18E tires, inflated to 65 psi. The rear GAWR is 7,000 pounds when the rear tires are inflated to 80 psi.
Shopping by the Numbers
Once you know the vehicle’s tow and payload ratings, you can begin shopping for a trailer. Whether you’re looking at travel trailers or fifth wheels, the most important consideration is how much it weighs. All trailers should have a yellow label that displays the unloaded vehicle weight (UVW), the gross vehicle weight rating (GVWR) and the cargo carrying capacity (CCC), which is established by subtracting the UVW from the GVWR. It’s important to note here that the UVW may vary depending on how the trailer is equipped, and you can’t determine its actual weight until it’s full of water (if you travel with a full freshwater tank) and all supplies you normally carry (learn more in “Worth the Weight” elsewhere in this issue).

Whether you’re shopping new or used, it’s unlikely that you’ll be able to weigh the trailer in its loaded condition before purchase, so your safest bet is to use the GVWR as your guide. As with the tow vehicle, the GVWR represents the maximum allowable weight — so if the trailer GVWR is within the tow vehicle’s maximum tow rating, it should be capable of towing it. Also, since it’s unlikely you will load the trailer to its maximum (though it is possible), using the GVWR as your guide can help you make sure that the tow vehicle has capacity to spare.

For example, you’ve established that your truck has a tow rating of 17,000 pounds. The trailer you’re considering has a GVWR of 16,980 pounds, and after subtracting the UVW and water has a CCC of 1,270 pounds. If you anticipate carrying 500 pounds of cargo, for example, you’ve got 770 pounds to work with before your tow vehicle is at its maximum tow rating, or a margin of about 5%. A margin of 10% (or more) is considered ideal, but as long as the tow vehicle isn’t at or over its towing limit, it will perform as intended.

A travel trailer places at least 10% of its weight on the vehicle’s hitch (known as hitch or tongue weight), while a fifth wheel will put around 20% of its weight in the bed of your truck (pin weight). Calculate that figure on the trailer you’re considering as if it were at maximum weight, then add up the passengers and typical cargo, and make sure the payload rating isn’t exceeded first. The next thing to consider is the vehicle’s gross axle weight rating (GAWR), which is the maximum weight the axle(s) is designed to carry. Unless you plan to haul a lot of weight in the bed of the truck, like a couple of quads, a generator and some firewood, exceeding the GAWR with a travel trailer usually isn’t a concern. However, because fifth wheel and gooseneck trailers carry more weight in the bed, directly over the truck’s rear axle, it’s important to make sure the GAWR is within range, especially when using a “half-ton” pickup to tow a fifth wheel.

Chevy’s Trailering Information label
Chevy’s Trailering Information label, introduced for the 2020 model year, is a great source of information for RVers. Not only does it display GVWR, GCWR, rear GAWR, curb weight and maximum payload, but for the first time in history this label also displays specific towing information for each vehicle. These first-generation labels were hard to read, but this one indicates “Conventional TWR” (trailer weight rating) is 14,500 pounds, with a maximum tongue (or hitch) weight of 1,450 pounds. “Gooseneck TWR” (or fifth wheel TWR) is 16,600 pounds, with a hitch weight (which in this case is actually pin weight) of 2,480 pounds. This label makes it easy and fast for buyers to determine whether or not a truck they are considering can handle the intended loads.
tire and loading information label
According to the Association for the Work Truck Industry (NTEA) Federal Motor Vehicle Safety Standard (FMVSS) 110 requires all new vehicles with a gross vehicle weight rating (GVWR) of 10,000 pounds or less, manufactured after September 1, 2005 (2006 and newer model year vehicles), have a tire and loading information label (also known as a vehicle placard) affixed to the driver’s door jamb. This label clearly states payload information with the statement, “The combined weight of occupants and cargo should never exceed…” followed by recommended inflation pressures for the tires the vehicle was originally equipped with. This is why, when it’s time for new tires, it’s important to seek those of the same size and specifications — or load carrying capacity can be compromised.
Trailer First
So far, we’ve discussed choosing a trailer when you already have a tow vehicle. However, some RVers begin their towing odyssey by selecting the perfect trailer, then finding the right vehicle to tow it with. In this scenario, it’s important to consider what tow vehicle will be required to tow your dream trailer, especially if you are new to towing. The heavier the trailer, the more capable the tow vehicle will need to be. A bigger, more powerful engine option, heavy duty towing/payload package and factory towing aids will raise the price tag — and if you’re shopping for a fifth wheel, you should also think about how comfortable you (and perhaps your partner) are with driving a heavy-duty truck or dually on the highway, in the city or even as a second family vehicle. Heavy-duty-labeled trucks are longer, require more room to turn and can ride relatively rough when they’re not towing/hauling anything. They are also more expensive than lighter trucks, get poorer fuel economy and may cost more to maintain.

With that in mind, once you’ve settled on a trailer, shop for a tow vehicle that is more than capable of towing it. If your new fifth wheel trailer has a GVWR of 20,000 pounds, you’ll want a vehicle that can tow at least that much. Due diligence falls squarely on the buyer’s shoulders here — don’t rely on the word of a salesperson who may or may not understand tow or weight ratings.

The good news is, it’s easy to do your own research on a new tow vehicle, as mentioned earlier. As part of your research, you’ll also want to check out the tow vehicle’s GVWR, GAWR, gross combined weight rating (GCWR = the maximum allowable weight of the truck and trailer) and payload to make sure it’s up to the task of towing your new trailer. Usually, a vehicle that has a sufficient tow rating will also have enough capacity in these other areas, but not always. For example, a half-ton truck may be rated to tow more than 12,000 pounds, but a fifth wheel weighing that much may exceed the payload and/or GAWR of the truck.

weight information
Although truck campers don’t have tires, they still include important weight information to help determine if it’s a good match for your pick-up. For example, this camper’s stated weight is 2,348 pounds with standard equipment, 33 gallons of freshwater and 5 gallons of LP-gas on board. Note that the stated weight is with standard equipment. Options like an air conditioner, additional batteries/LP-gas cylinders and the like will add weight, as will any cargo carried in the camper itself. Before purchase, you would want to add up the weight of the passengers and cargo that go along with you, then add camper’s stated weight to the equation and make sure the truck’s payload rating is not exceeded. You would also want to weigh the truck to make sure the rear GAWR would not be exceeded once the camper was on board.
GAWR/GVWR ratings
Travel trailers and fifth wheels must also display GAWR/GVWR ratings and payload, as well as cold inflation pressure for the tires the unit was originally equipped with. In the case of trailers, the weight label also includes cargo carrying capacity (CCC) calculated with the freshwater tank full and the gray/black holding tanks empty. This particular trailer GVWR is 9,630 pounds, so ideally, you would want to pair it with a truck or SUV that could tow 12,000 pounds or more to maintain a safe margin.
Single or Dual?
Once you arrive at a fifth wheel that weighs north of 15,000 pounds, you may find yourself wondering if a dually is necessary, or if you can get by with a single rear wheel (SRW) heavy-duty truck. While it is true that there are SRW trucks on the market today that can tow more than 20,000 pounds, a dually offers more than just a higher tow rating. The truck’s extra set of rear wheels gives it substantially higher payload and GAWR ratings, keeps the truck more stable in sidewinds or when being passed by semi tractor-trailers and gives you a greater safety margin in the event of a rear tire blowout. Choosing a dual-rear wheel option doesn’t add much to the price tag, either.
Truck and trailer parked next to body of water
Photo by Karen Dougherty
Modern construction methods and technology have made fifth wheel trailers lighter, which means many can be safely towed by a single rear wheel (SRW) 3/4-ton or one-ton pickup.
On the other hand, a dually is wider and more difficult to park (especially in the city), takes up more room in the driveway, garage or RV site and requires extra caution when rounding tight corners to prevent damage to the fender extensions. More tires means increased rolling resistance, so you’ll typically experience reduced fuel economy compared to an SRW truck when driving solo (differences in fuel economy while towing will generally be marginal), and that extra rubber will also mean additional cost when it’s time for new tires. Also, dually trucks cost more to register and are subject to higher tolls on highways.
How are Tow Ratings Established?
Prior to 2008, vehicle manufacturers could assign their own tow ratings to a vehicle, which sometimes led to performance expectations for the buyer that were not met. It almost goes without saying that a tow rating is established by a number of factors, ranging from the obvious (engine power and torque) to lesser-known considerations like suspension components, cooling system performance, braking capability and more. In fact, it was often said that a tow rating was based on the weakest link in the entire mechanical ensemble, which is why it’s possible to increase a vehicle’s towing performance (by changing the final drive ratio, adding an exhaust system, etc.), but not its tow rating.

In 2008, the Society of Automotive Engineers (SAE) published its J2807 standard, designed to level the playing field when it came to tow ratings. It was expected to be adopted by all truck manufacturers by the 2013 model year, but it wasn’t until 2014 that all manufacturers came to the table to adopt it for 2015. The standard is extremely detailed but includes driving repeatedly up a 12% grade for a specific distance with trailer attached in both forward and reverse; an acceleration test in which the tow vehicle and trailer must be able to reach 0-30 mph and 0-60 mph in a specified period of time; and towing a steep grade (or simulated dynamic grade) at 100 degrees ambient temperature with the air-conditioning on full blast without any cooling system or other component failures. There are also braking and handling tests involved. Once testing is completed and a truck/SUV meets all of the necessary criteria, the basic calculation for the SAE maximum tow weight rating is: GCWR minus tow vehicle total weight (TVTW), which includes the weight of the driver, passengers and equipment.

With J2807 in place, you can be assured that a vehicle really can tow what the manufacturer claims.

Toy Hauler Weight and Loading
Unlike conventional travel trailers and fifth wheels, toy haulers are designed to carry hundreds, or even thousands of pounds behind the wheels, which makes determining loaded hitch weight a challenge for both the manufacturer and the end user.

“We maintain a heavier starting range on travel trailer and fifth wheel toy haulers in anticipation of the offloading that will occur when the garage area is loaded,” explained Mark Bullock, senior vice president of engineering for Keystone RV. “Instead of the normal 10% – 15% for travel trailers, we specify an initial build range of 13% to 17%, anticipating that the loading in the rear garage area by the customer will place the final hitch percentage within the accepted normal range of 10% – 15%. For fifth wheels, we specify an initial build range of 22% – 25% rather than the normal 15% – 25%, expecting the same result. Leaving a starting hitch range at 10% for a toy hauler travel trailer (for example) can mean a loaded hitch percentage of 2% or 3%, depending on the load rating of the rear garage area, location of the water tank, whether it is filled or not, etc. That isn’t safe.”

Since the trailer axles act as a fulcrum, or point at which the trailer pivots, toy hauler owners should be aware that the load placed in the rear cargo area is actually going to off load, or lighten, the total weight on the hitch or pin, which can dramatically change the hitch weight — more so than in a conventional RV. “This presents a design problem that can be difficult to overcome,” Bullock said. “If the cargo area has a rating of 1,000, 1,500, 2,000 or even 3,000 pounds, and that area can either be fully loaded, or not loaded at all, that kind of variability is difficult to design for.

full-size fifth wheel toy hauler
A full-size fifth wheel toy hauler like this Keystone Raptor provides a comfortable place to stay even in the middle of nowhere. Because of a hitch weight that can exceed 3,000 pounds, a dually is usually the best choice for towing one of these bad boys.
“The location of other significant weight components such as water tanks, for example, can also have an impact,” he added. “Some of these tanks hold more than 100 gallons (840 pounds). Fuel tank(s) are generally in the rear, too, but not always filled before a trip. This becomes another factor that can vary, as well as the customer’s general cargo loading. It’s a balancing act and there are lots of factors, and since no two customers load their toy haulers the same way, we aim to strike a balance that can hopefully satisfy everyone.”

As with conventional trailers, Keystone (and other manufacturers) provide labels that specify the maximum load capacity of the cargo area, and also include a detailed explanation of how to properly load the cargo area in the Owner’s Manual.

“What we see most often when it comes to cargo is that the customer typically underestimates how much weight he or she is adding,” Bullock continued. “This goes for conventional trailers and fifth wheels as well, but the problem is exacerbated with a toy hauler due to the larger cargo areas provided. A lot of time the perception is ‘if it will fit inside let’s take it.’ But there is no easy solution to knowing how much you’ve added without weighing the loaded trailer.”

Full-size fifth wheel toy hauler with people on motorcycles
Full-size fifth wheel toy haulers offer massive cargo areas, designed to carry anything from several dirt bikes and quads, to street bikes, side-by-sides, or a combination of all of these toys. Understanding the weight of each toy, along with all the gear you bring along, is important in determining not only actual trailer weight, but hitch/pin weight as well. Remember, just because the cargo fits doesn’t mean capacity can’t be exceeded; four touring bikes like these can weigh 3,000 pounds or more.
That’s a difficult proposition if you are in the market for a toy hauler, so what’s the solution? As with other trailers, look at the GVWR of the toy hauler you are considering and make sure it doesn’t exceed the tow rating of the truck. The hitch weight should also be specified, which is usually based on the average weight of the standard build. As mentioned earlier in this sidebar, the hitch weight will be reduced when cargo is added to the rear but using the average unloaded hitch weight as a guide will help you determine if your payload capacity, GAWR or GCWR are within range.

Once the trailer is in your possession, take it to a scale, loaded and ready for travel to determine the exact overall and hitch weight of the rig. Better yet, call a shop that specializes in RV/truck/trailer alignment (and other services) and ask if they can determine individual wheel weights (see “Worth the Weight” elsewhere in this issue for more information). This will not only tell you overall weight, but also how that weight is balanced, which can be a useful reference when loading.