How Large an RV Can Your Vehicle Tow?

Determining the maximum weight your vehicle can tow is more complex than it immediately seems. However, it is important to understand the details because towing beyond your vehicle’s capability can damage your vehicle, the trailer, or both. It is likely to cause you considerable stress on the road and possibly pose a threat to others on the road with you.  The Dieffenbach GM Superstore wants you to be safe and confident whenever you tow, so take some time to be aware of all the necessary considerations.

Trailer Maximum Towing Capacity is Just the Beginning

Your vehicle will have a maximum towing capacity rating. Remember that while marketing information often gives a maximum towing rating for the model line, it varies by vehicle configuration. The towing capacity will diminish with increases in the vehicle’s weight for a given model. Consequently, 4×2 models will generally tow more than 4×4 models. Regular cabs will have a higher rating than crew cabs, and higher-equipped models will typically weigh more but tow less than more basic-equipped models.

One exception to the last point is a towing package. In addition to providing a hitch and wiring for the trailer’s lights and brakes, these packages will usually provide more robust cooling systems for both the engine and transmission, a possibly revised axle ratio, and other towing-focused features, which will increase the vehicle’s towing capacity. Nevertheless, your owner’s manual will have a table that should allow you to identify your vehicle’s maximum towing capacity.

The next consideration is the trailer’s weight, which should be easy to determine. Any documentation should expressly state this information, and the trailer’s Vehicle Identification Number (VIN) plaque should also provide this information.

Your vehicle’s towing capacity should be higher than your trailer weight. However, you are not ready to hitch up yet. You’ve just done the easy part.

There is “Stuff” to Consider

Now, you must figure in your stuff; that is the additional weight of everything you take.  First, there is all you are bringing in your towing vehicle. This will include fuel, the combined weight of all the passengers, plus everything you bring with you in the vehicle, such as luggage, a cooler of drinks, and, of course, pets. Then, there are all the things you want on hand, such as tools and spare parts. You are estimating the Gross Combined Vehicle Weight (GCVW).

Next, you have to estimate the weight of all that is being added to the trailer. If you are towing an RV, this will be everything you store inside, including clothes, cookware, tools, tank fluids, outdoor grilles, bicycles, e-bikes, or any other recreational equipment. You will want to ensure everything is within the trailer’s Cargo Carrying Capacity (CCC). Fortunately, your RV is likely to have a high enough CCC to cover everything you want to bring. But if you are adding things to the roof or if the trailer has a toy box space in the rear for an ATV or whatever, that will all need to be considered as well.

Remember that if you are towing with an SUV, you are likely to load up the cargo area. If your tow vehicle is a pickup truck, you are likely to store more in the trailer for security reasons, and of course, if you tow a fifth-wheel trailer, almost everything will go in the trailer by default. In any case, you will want to ensure that what you carry in the vehicle does not exceed its payload capacity, which will also be in your owner’s manual.

Estimating the weight of your stuff is understandably a challenge. You are not likely to weigh every single item and add it all up. The best you can do is determine the weight of the larger items and estimate the rest, but it is wise to overestimate. If you can access a vehicle scale, it may be worth your time to weigh a fully loaded trailer. Even if you are thinking of getting a different trailer, you may know how much you generally take with you. Remember, the bigger the RV, the more you are likely to put in it.

Other Considerations

You should also consider if your tires are up to the load of your tow vehicle and the trailer. This goes double if you replaced your tires at some point.

Another consideration is tongue weight. This is the downward pressure on the trailer hitch and, thus, the rear of your tow vehicle. RVs are designed not to have an excessive tongue weight, but that can change depending on how you store your cargo. If you are approaching but still within your tow vehicle’s towing or tongue weight capacity, consider a weight distribution hitch, which helps spread the weight from the rear to the front of the vehicle. You also want to make sure your trailer rides level where neither the tongue nor trailer rear bumper is pointed toward the ground. Trucks raised for off-roading often need a height-adjustable trailer hitch to ensure the trailer ride level.

Terms

Because we’ve thrown several weight terms and acronyms about, here is a list of trailering relevant weight terms and their definitions:

Curb Weight —The curb weight of your vehicle is its weight with all of the standard equipment and necessary operating consumables (e.g., motor oil and coolant) and a full tank of fuel but without any passengers, cargo, or any other separately loaded items in it.

Gross Combination Weight Rating (GCWR) —This is the maximum allowable weight of the tow vehicle and the trailer combined. The GCWR may be found in the Owner’s Manual or in the tow vehicle brochure for the model year you own, usually provided by the dealership. Some late-model vehicles may have a “Trailering Information” label providing the GCWR. The GCWR assumes that the tow vehicle and trailer have functioning brakes, with exceptions for very light trailers (typically less than 1,500 pounds).

Gross Vehicle Weight Rating (GVWR) —The GVWR is the maximum allowable weight of the fully-loaded vehicle, including liquids, passengers, cargo, and kingpin or tongue weight of any towed trailer. The GVWR is printed on the certification label and usually near the driver’s side door. This information can be found on the Trailering Information label on some late-model vehicles. GVWR primarily considers the weakest link in the load-bearing components, such as the frame, axles, springs, brakes, rims, and tires. Based on the lowest component rating within the load-bearing components, manufacturers assign the GVWR.

Gross Vehicle Weight (GVW)—The vehicle’s combined weight with all expected passengers, including cargo, a towing hitch installed, and full fluid tanks.

Trailer Weight Rating (TWR) —This is the rated value for the maximum allowable weight of a loaded trailer for a specific tow-vehicle model and hitch type, as determined by the tow-vehicle manufacturer. A specific tow vehicle may have multiple TWRs for weight carrying, weight distributing, fifth wheel, and/or gooseneck hitch. A tow vehicle may also have a TWR for an unbraked trailer.

Tongue Weight (TW) — The vertical load weight applied to a hitch. It should generally range between 10% to 15% of the trailer’s GVW.

Pin Weight (PW) — This is the same as TV but for fifth-wheel trailers. Ideally, fifth-wheel trailers should range between 15% to 25% of the trailer’s GVW. The closer to 15%, the better.

Tow-vehicle Trailering Weight (TVTW) —Base vehicle curb weight of an estimated 150-pound driver and one 150-pound front seat passenger, plus100 pounds of optional equipment split evenly between front and rear axles, plus the tow-vehicle manufacturer’s available trailering package and/or any required trailering content and representative aftermarket trailering equipment.

Tow Ready Vehicle/Truck —The fully-loaded vehicle or truck with the driver and all passengers on board, all desired cargo onboard, necessary trailering equipment installed, and necessary vehicle fluid tanks or reservoirs filled to standard or full capacity.

The Dieffenbach GM Superstore expects many of its GMC customers to use their vehicles for towing, and we hope this brief tutorial was helpful. Our Service Center is another useful resource for customers with towing questions, so don’t hesitate to ask.