For motorhome owners, embarking on a road trip often involves towing extra cargo, vehicles, or recreational gear. However, not knowing your motorhome's towing capacity can lead to dangerous situations and costly damages. Understanding load ratings, gross weight, and safety limits is crucial to ensure a safe and enjoyable journey on the road.
In this guide, we’ll explore how towing capacity and tongue weight capacity works, why it's so important, and how you can find your motorhome's tow capacity at home. Whether you’re planning to haul a trailer, cargo carrier, or additional equipment, knowing these figures can make the difference between a smooth trip and a towing nightmare.
Towing capacity is the maximum weight your motorhome can safely and legally pull, including the weight of the trailer and its cargo. Towing capacity applies to situations where a trailer or another wheeled tow accessory is hooked up to the receiver hitch. It’s determined based on the pulling power of your vehicle's engine, transmission, and other parts. If you exceed your towing capacity, you risk overloading your motorhome, which can lead to reduced performance, damage and safety hazards.
Motorhome owners often use their vehicles to tow extra gear such as cargo trailers, boats, or even other vehicles. Understanding towing capacity is essential to avoid putting too much strain on your motorhome. Overloading can lead to engine failure, brake issues, and in the worst-case scenario—accidents.
The biggest and most important misunderstanding when it comes to towing is assuming that the trailer’s weight alone is the most important factor. It is important to also take into account the cargo inside of the trailer you hauling to properly calculate overall towing capability.
The acronyms GVWR, GCWR, and GAWR (explained below) are critical load ratings that determine how much your motorhome and its axles can handle. These figures are essential to calculate the total towing capacity and you keep your vehicle within safe operational limits, preventing mechanical strain and potential hazards.
The Gross Vehicle Weight Rating (GVWR) is the maximum weight a motorhome can handle, including passengers, cargo, and fuel. While the GVWR is not the vehicle's tow capacity, the gross weight rating is a significant factor in ultimately determining towing capacity because exceeding it compromises the motorhome’s ability to control the towed load.
The Gross Combined Weight Rating (GCWR) is the total weight your motorhome and the towed vehicle can handle together. This includes the weight of the motorhome, the trailer, and anything being carried in either. This figure helps RV owners know their absolute limits when towing.
The Gross Axle Weight Rating (GAWR) is the maximum capacity of each axle of your motorhome (or trailer). As opposed to the vehicle overall, this weight rating applies to how much each axle individually. The front and rear axle on your RV will have different weight ratings.
Tongue Weight (TW) is the downward force exerted by either a trailer or hitch carrier on the hitch receiver. It's a key number in towing and it is especially important when transporting hitch accessories like bicycle carriers and cargo carriers.
When towing a trailer, tongue weight should be around 10-15% of the total loaded trailer weight. A tongue weight that’s too light can lead to trailer sway, while one that’s too heavy can overload your motorhome’s rear axle.
Since hitch carriers, such as bike racks and cargo carriers, do not have axles to support their weight, your motorhome relies entirely on the vehicle's tongue weight capacity (TWC) to transport the racks. If your hitch was factory installed, you can usually find your TWC in your vehicle owner's manual.
If your receiver was not factory-installed, or you are only able to find the vehicle's and hitches GVWR (mentioned above), you can calculate your TWC by multiplying your motorhome's GVWR maximum towing capacity by .10 (ten percent). Using this equation (TWC = GTWR x .10) we can see that a hitch with a 7500 lbs towing capacity has a tongue weight capacity of 750 lbs.
In the towing industry, there’s a "20% rule" often cited by trailer dealers and off-road professionals alike. This rule of thumb implies that when determining safe load limits, you should account for at a 20% reduction in the maximum weight carrying capacity for every 1ft rearward the carried center of gravity extends from your motorhome's hitch face. It's important to recognize that the addition of extensions, adapters, and other hitch accessories greatly affects the leverage and load force that is exacted on your vehicle's hitch.
For example, Let’s Go Aero’s enclosed hitch carriers are rated to carry a maximum of 300 pounds. However, industry standards recommend that when using any type of cargo carrier, you should factor in additional forces such as your vehicle hitch class that may reduce this capacity. Hitch extensions or adapters, for instance, can increase leverage and load forces, potentially reducing the actual usable load to less than the rated capacity. In some cases, a hitch with a lower load rating may not be able to handle the full rated capacity of a cargo carrier.
For example, our BlackBox Cargo Carrier weighs 175 lbs empty and rated for up to 300 lbs. A Class III hitch has (on average) a 500 lbs tongue weight rating. When you do the math—not accounting for the 20% rule— it sounds like you should be able to enjoy the full 300 lbs capacity of the carrier, right?
Well, maybe not.
When we look at where the load force (or our cargo) is when inside the carrier we can imagine it is about 18in from the rearward face. At 18in we are looking at about a 30% reduction in weight capacity which would leave us with just 175 lbs of load capacity inside the carrier.
Though is not a "hard rule", the 20% buffer allows for a margin of safety, ensuring that factors like hard road bumps, weight shifts, and hitch forces don’t compromise your motorhome’s towing stability. Always keep this industry standard in mind when calculating your towing capacity for a safer towing experience.
Manufacturers provide these detailed load ratings, axle ratings, and towing capacities to ensure safe towing. Ignoring these specifications or improvising with your own d.i.y. mounting can lead to equipment failure and unsafe conditions on the road.
Many manufacturers and dealers like Camping World provide towing calculators online. Some apps also allow users to input the motorhome’s specifics, such as the GVWR and GCWR, for real-time calculation. Using these tools ensures precise results.
Don’t forget that every extra person, gallon of water, and piece of equipment adds to your overall weight. You must factor in not only the weight of the trailer and its contents but also the weight inside the motorhome.
Regular inspections of your motorhome’s hitch, tires, and brakes are crucial for maintaining towing safety. This is especially important before long trips, where towing stress can compound over time.
Never overload your motorhome, and don’t assume a hitch alone can support any load. Always respect load limits, and avoid making quick lane changes, hard braking, or sharp turns that could destabilize the towed vehicle.
Exceeding towing capacity can result in engine overheating, transmission failure, and brake malfunctions. In worst-case scenarios, towing too much can cause parts to bend and the motorhome to lose control, leading to dangerous swerving or jackknifing on the highway.
Understanding your motorhome’s towing capacity is not just about avoiding legal trouble—it's about ensuring a safe, enjoyable trip. By calculating your load ratings and sticking to the manufacturer’s guidelines, you can tow confidently and protect your vehicle from unnecessary damage.
