“What can I tow?” and “Can I tow that?” (with my truck, SUV, car, minivan) are two of the most common questions that people have. A slightly worse question is, “I’ve bought this trailer, will my truck tow it?” because then you’re a little more stuck. But, let’s go with the optimists route:
- You have a SUV, truck or van
- You are just starting your RV search
- You want to be safe and stay within your limits
More times than not, the single most important limiting factor is your truck’s available payload.
Payload is the difference between the maximum your truck can carry minus the weight of the truck. Generally the payload plans for a 150 pound driver and a full tank of fuel. The “rest” of your driver, all passengers and everything you carry eats into this payload number. Whatever is left over is what you can use for tongue weight for bumper-pull trailers or pin weight for fifth wheels. We’ll talk more about all of these things later.
There are 2 ways to approach the “What can I tow?” question and both revolve around the weight of your truck and the things in it. For trucks about 2005 and newer, you should have 2 different stickers on the truck – usually on a doorjamb. See below for my stickers from my 2012 Dodge Ram 3500 with dual rear wheels:
Approach #1 – Weight Ratings and Getting Weighed
The first sticker showing the Weight Ratings is used by combining that with actually having your truck weighed at a scale of some sort (via a truck stop/CAT Scale or by going to a quarry, dump, etc.). To prepare for this weighing, you should load the truck as if you were going for camping with your usual supplies:
- Your driver
- Your passengers (with infant/child seats, booster seats, etc.)
- Any food, snacks and drinks
- Any games, toys, activities and diaper bags for the kids
- Guides, maps, travel directories
- Firewood, generators, camping chairs, tables, and other supplies
- And, of course- your hitch
When you go to the scale, you will get a weight that tells you what your total vehicle weight is. The number on the sticker that is most important to you is the one that tells you what the maximum weight that the truck can handle. This is called the Gross Vehicle Weight Rating (GVWR). You would take the GVWR and subtract the weight of the truck from the scale. What’s leftover is how much you tongue or pin weight you can carry (again, more on this later).
By far, this is the best method as it takes all of the guess work out of play.
Approach #2 – The Cargo Carrying Capacity
The second sticker showing the Cargo Carrying Capacity gives you an alternate way of figuring out your towing capacity. In fact, on some vehicles (like my father-in-law’s Toyota 4Runner), this is all that he has. The number on this sticker that is most important is the “The combined weight of of occupants and cargo should never exceed XXX kg or XXX lb”. From this number, you have to subtract all of the same things that I listed above (driver, passengers, foods, activities, maps, camping supplies and hitch). (Note: most people assume that a 150 pound driver or 150 pounds for each seat belt is already included in this number. I was just reading the Owner’s Manual for my truck and it didn’t make any such claims. I was kind of surprised.) Again, what is left over is what you can carry in tongue or pin weight.
Ok, now I know my payload – what does it mean?
Knowing your remaining payload capacity is paramount to knowing how much camper that you can tow and stay within your vehicle’s limits. The RV connects to your truck via a hitch – either a bumper pull or a fifth wheel. This connection puts weight onto the back of your truck and has to be accounted for. That’s why we did all of the measurements up above – we wanted to ensure that you had enough leftover payload to handle this weight. For a bumper-pull (travel trailer, pop-up camper, hybrid or A-frame), this is called tongue weight. For a fifth wheel, this is called pin weight.
For bumper-pulls, you’re generally targeting 13% to 15% of the camper’s total weight to make the RV behave best. For fifth wheels, you’ll generally find 20% – 25% of the camper’s total weight is pushing down in the bed of the truck.
Which Trailer Weight to Use
When you walk through a RV dealership, or go to a show, or look at a brochures – you see big signs plastered everywhere that say, “This camper weighs X lbs!” When push comes to shove, this is generally the “unloaded vehicle weight” (aka- “dry weight”) of the camper. Meaning it’s usually before options are added or necessities like propane and battery(ies) are added. And, of course – it’s impossible for them to know how much stuff that you’re going to add (clothes, linens, toiletries, food, pillows, camping gear, you name it). The true and unchanging number is the maximum weight that the camper is allowed to weigh called the “gross vehicle weight rating” (GVWR). Basically, if you’re safe for the GVWR, you’re safe for anything less than that.
(Note, many manufacturer’s websites aren’t as up-to-date or filled-in as we’d like. Many times, they show “TBD” for the GVWR but do show values for the “unloaded vehicle weight” and “cargo carrying capacity”. You can deduce the GVWR by adding these two values together.)
To calculate the tongue weight, you should take the GVWR and multiply it by .12 and .15 and that is your range of what your tongue weight could be, at most. Note, my calculators do this for you.
To calculate the pin weight of a fifth wheel, you do the same only with different multipliers. You should take the GVWR and multiple it by .2 and .25 and that gives you your range. Note, my calculators do this for you.
You need this tongue/pin weight number to be less than your vehicle’s remaining payload.
I have blogged about helping my father-in-law figure out the real towing capacity of his Toyota 4Runner. Read now…