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RV engineer spills the dirty truth about RV cargo capacity

In the alphabet soup of RV towing capacities, Cargo Carrying Capacity (CCC) is usually overshadowed by Gross Vehicle Weight Rating (GVWR), Gross Combined Weight Rating (GCWR), Gross Axle Weight Rating (GAWR) …

All right, I’ll stop! No sense in shoving alphabet soup down your throat until you vomit it back up. But you should really know more about your RV cargo capacity, because …

“But, Ross,” you interrupt, “that’s techno-talk. That’s for RV nerds (no offense). I’m just shopping around!”

Then you are EXACTLY who should be reading this post! Most buyers don’t pay attention to that little black-and-yellow sticker until AFTER their purchase, and by then it’s $75,000 too late.

What is RV cargo weight and how is it calculated?

RV cargo weight is how much “stuff” you can add before overloading the RV.

Calculating cargo capacity is governed by the FMVSS 110 and FMVSS 120 standards.

The simple equation is: CCC = GVWR – UVW

  • Where GVWR = Gross Vehicle Weight Rating, or the maximum scale weight of a fully loaded RV.
  • Where UVW = Unloaded (or Unladen) Vehicle Weight, which is the weight of the RV, plus operating fluids, as configured for delivery to the dealership. This will include forced options as well.

PUBLIC SERVICE ANNOUNCEMENT: A lot of the other so-called “RV blogs” are WRONG about Cargo Carrying Capacity! They’ll share an equation that’s been obsolete since 2008. Today, water, occupants and stuff are all considered “cargo,” and you’re responsible for tracking their weight.

Sounds simple, right? Well … there is a lot of fine print.

RV cargo capacity: What you need to know!

Let me do my part to clean up some of the myths and misconceptions about RV cargo weight capacities. Here are four things you should know:

1. Cargo labels are accurate to within ~100 lbs.

Dealers are allowed to add up to 100 lbs. or 1.5% of the GVWR (whichever is less) to the RV without replacing or correcting the CCC label.

This is because dealers commonly add batteries and small accessories to the RV. Because tires are not sensitive to very small overloads, NHTSA has allowed dealers to add accessories without the hassle of swapping stickers.

2. Propane and fuel are included in the base weight

The UVW includes the weight of full propane and fuel tanks.

That’s good news! In other words, the law assumes that propane is as critical to your RV as gasoline is to a car. So the weight of that propane is built into the base weight; you don’t need to track it separately.

Same thing with fuel: Gasoline and diesel are already included in the unladen weight.

3. Water and occupants are considered payload

… But water and occupants are treated as cargo.

This is why all RVs have a sticker explaining that water weighs 8.3 lbs. per gallon. That information helps you estimate the remaining cargo capacity after filling your freshwater tank (and don’t forget the water heater tank!).

^Now, this rule causes lots of confusion. Let’s see how the math plays out:

Example: If your RV has, say, 1,000 lbs. of cargo capacity, what’s left after filling your water tank (6 gallons) and freshwater tank (30 gallons)? We’ll ignore the water in the supply lines.

Eq: 1,000 – (6+30)*8.3 = 701 lbs.

So you’ve reduced your payload capacity by 300 lbs. just by filling up your tank! And if you were also carrying 15 gallons of black water and 20 gallons of gray water to the nearest dump site, you would only have 410 lbs. of payload left. Yikes!

4. The CCC sticker is law!

The CCC sticker isn’t just there for legal reasons.

As Tony Barthel shared in his post about dangerously overweight RVs, some salespeople told him that “the chassis are designed for much more than the sticker says.”

That is grossly inaccurate, deceptive, and dangerous. In my experience, RV manufacturers aren’t in the habit of arbitrarily knocking down capacities just to play it safe. We’re trying to make use of every pound we can!

And why does the salesperson think he can decide what the “real” cargo capacity is? Did he specify the axles? Did he calculate the tire reserve capacity? And did he run an FEA stress analysis on the frame? No??? I didn’t think so!

The dirty truth about RV cargo capacity

Here’s an unfortunate truth: CCC stickers don’t sell RVs. Cabinets do. People are like honeybees: We love to see little pockets full of goods and goodies.

So when you walk into a rig, what’s the first thing that catches your eye? Cabinets, cabinets, cabinets! The hidden sliding drawer beneath the dinette, the overhead cargo netting above the bed, the cavern beneath the master bed. And we haven’t even talked about the pass-through basement garage, the bike rack, the 300 lb. rear hitch…

But did you know that just filling your cabinets and storage spaces could overload your RV? 

Here’s what Forest River says:

Did you catch that? “You cannot necessarily use all available space when loading your unit.” Not unless most of your luggage is down comforters and bags of marshmallows, that is.

I would humbly argue that a significant number of RVs are built with inadequate RV cargo capacity. I think the problem is worst on:

  • Travel trailers longer than 30 feet
  • Extended Class C motorhomes, especially those on a 12k or 14.5k chassis
  • Gasoline-powered, front-engine Class A motorhomes
  • Any “ultralight” camper with 2+ slide-outs

But don’t lynch the manufacturer just yet! Yes, it’s easy to blame the builder—and they certainly are culpable. I’m not denying that. But when the customer keeps begging for higher towing capacities, for more slide-outs, for tile floors and dual air conditioners and not an inch of wasted space, then don’t be surprised when you get what you asked for. Et tu.

What’s a good cargo carrying capacity for an RV?

Pounds are like potato chips: One doesn’t seem like much, but when one follows the other—wait, where did the bag go?

Just remember how difficult it is to shrink your luggage to 40 lbs. for a checked bag on a plane!

I recommend at least 1,700 lbs. cargo capacity or 500 lbs. per person, whichever is greater. This is the minimum—more is better!

  • If you’re a full-timer, add 50%.
  • If you’re a boondocker or adventurer, add 25%.
  • If you plan on towing a second vehicle with your motorhome, add the tongue weight of the toad, dinghy or car hauler.
  • If you have a toy hauler, the weight of the toys should be added separately.

For some other back-of-the-envelope math, I’ve created the following graduated scale, where the minimum CCC should be:

  • 25% of the GVWR for RVs below 10,000 lbs.
  • 20% of the GVWR for RVs between 10,001 lbs. and 19,999 lbs.
  • 15% of the GVWR for RVS above 20,000 lbs.

To my knowledge, there is no minimum CCC legal regulation. So long as the RV manufacturer has met the tire loading requirements, CCC is left to their discretion.

I would not purchase an RV with a payload capacity of 1,000 lbs. or less unless it was a mini travel trailer (e.g., Scamp) or teardrop trailer.

Big takeaways for the RV owner

I’ve thrown a lot at you in the past 1,200 words. Here are the big takeaways:

  1. Don’t assume your RV can carry what you think it can based on storage space.
  2. Extended Class C’s, gasoline-powered Class A’s, and 30-ft.-plus travel trailers are the usual suspects.
  3. Get the cargo capacity from the CCC sticker, not the salesperson.
  4. Remember that occupants and water will count against cargo.
  5. Plan on 500 pounds per person plus extra for toys.
  6. If the numbers don’t add up, keep shopping.
  7. Weigh your RV after loading to double-check your estimates!

##RVT1077

Ross Regis
Ross Regishttps://askthervengineer.com/
Ross Regis is an advanced RV technician and design engineer specializing in towables. Jack of all disciplines and master of none, Ross enjoys explaining how RVs work (and sometimes why they don't). He blogs weekly at AskTheRVEngineer.com.

Comments

  1. Hi, I read with intrest that that at least one gas bottle and battery in included in the UVW, so I don’t have to add it to the items I place in the Travel trailer.
    If this is correct it’s a great help.
    I have a KZ SPORTSMEN CLASSIC 180QB… I can’t find anywhere in the manual or on the stickers to confirm this.
    Do you have any knowledge of tge KZ brand and if I am good to assume one gas bottle and battery are included in the UVW.
    Looking forward to your response.
    Rob …. RVTravels.

  2. We are looking at a smaller trailer to be towed with my SUV, which is rated for 500 lb.

    The trailer GVWR is 3,849 lb. The CCC is 571 lb. That equates to 14.8% so it is VERY low. The capacity of the 3 main tanks comes to 946 lb. (42 gal FW, 36 gal x 2 for B/G tanks). So, in effect… the manufacturer (Forest River) has produced a trailer that should not be on the road with the capacity they have put in.

    Now… 42 gal of fresh water is a LOT and I wouldn’t tow anywhere near that for the weekend camping we’d do. And as others have said I’d fill up the closer I get to where I’m going or find full service sites.

    This article opened my eyes as the whole idea of cargo capacities was really confusing. As much as I really do like the trailer we were looking at… it doesn’t add up. Will have to keep searching.

    • Sorry for the delay in approving your comment, Steve. I didn’t realize that our sometimes over-zealous spam filter put it into the Spam folder and I just noticed it. Any future comments you post should show up automatically. Have a good night. 😀 –Diane at RVtravel.com

  3. Great article — very helpful! We are considering going full time and I did not fully understand this issue until I read your article. I now see how anything below 2K CCC would be unworkable even for just two of us and a dog. Frankly, it now seems ridiculous to me how many Class B+ vehicles there are out there with < 800 lbs CCC — you almost need to have a second vehicle follow you around with everything you need! 😀

  4. Lite also effects cargo capacity. I found out I was going over the gvwr of the trailer. I was also at the limit or just over the cargo capacity of the truck so I couldn’t transfer weight there either. Had people suggest to transfer weight inside the trailer for better balance and they obviously didn’t understand that over gvwr is OVER, you can’t rebalance load to get below GVWR. Ended up upgrading my truck to a 1 ton and putting more in the truck. If I ever replace the trailer I will CAREFULLY look at the trailers cargo capacity. ON a side note, I never believe a salesman’s statements about what the truck can handle and I’m sure to ignore dry weights advertised and tongue weights as both are with NOTHING in the trailer.

  5. I’m unclear on why a “toad” adds 750 lbs to the ccc. It seems to me that the only weight added to the motorhome would be the tongue weight of the tow bar. I understand the added weight of the toad will effect braking, but that’s what the supplemental braking systems are for. What am I missing?

    • Apologies for my careless language! I will have the article revised. That should read “car trailer” rather than “toad,” because you’re correct: Flat-towing a vehicle via tow bar or dolly adds very little hitch weight, but towing a car hauler can add up to 750 lbs of hitch weight.

  6. My sticker does not address water tanks or propane tanks. The dealer was selling with one propane tank but I negotiated a second one and a second battery in my purchase so the weight of those would not be included in what the manufacturer put on the weight sticker.

    I never tow with a full tank of water. Just enough to be on the road for a couple of days flushing the toilet and brushing teeth if boondocking and so I don’t have to connect to water if I’m in a park overnight. If boondocking for a while I fill up close to where I’m staying so it isn’t towed the whole way.

    After full timing for two years I moved into my house and weighed everything I had been carrying around…almost 700#s over the CCC.

  7. 36 x 8.3lbs = 298.8lbs not 701.

    Plus, water is usually taken into account when determining cargo capacity as shown in the pic provided. 🙂

    Good article otherwise!

    • Ken, the equation is calculating the leftover CCC after subtracting the 299 lbs from the theoretical CCC of 1,000. So the 701 is accurate. I can see how the photograph could cause some confusion … that is a Canadian compliance label measuring Net Cargo Capacity, which is an obsolete term in the U.S. The CCC stickers of modern RVs do not include onboard water in the base weight per FMVSS 110 and 120 standards.

  8. One more item – RVs are often much heavier on one side than the other, so the wheel(s) on one side of an axle may be carrying much more than half of the axle weight. That is why getting individual wheel weights is very important. You may be under the GAWR, and still have a tire that is overloaded. Setting the proper inflation pressure for an axle requires that the load on each end is known, and the pressure set for the heavier load, plus something for reserve capacity.

  9. I am wondering who would have their fresh water tank, gray tank and black tank all full at the same time, as you figured at that top of the article? Don’t most people dump their tanks before they fill up the fresh water tank again?

    • Hello Barbie! The example given does not assume all tanks are full. As a worst-case scenario, it assumes full fresh water (30 gallons) and partially full black and gray (15 and 20 gallons). This is completely plausible for a camping family on an extended road trip who camps for a weekend at a site without sewer hookups, fills up the FW tank in preparation for tomorrow’s site, and drives to a dump station en route. That’s not common for people who camp with FHU, but for some boondocking campers, that’s pretty routine.

  10. No, a higher price does not necessarily equate to more CCC or OCCC. The Tiffin Wayfarer Class C is (in)famous for low OCCC’s, with people posting pics of their stickers of between 700 lbs and 1,000 lbs.

    The Wayfarer has an MSRP approaching or exceeding $200,000 and used ones typically are well over $100,000. A driver, a passenger, and a little water and stuff can overload a Wayfarer.

    But you’ll be a Tiffin owner! Or, rather, a Thor owner. 🙂

    • Pro Tip: Any RV with a long rear overhang is usually a candidate for inadequate CCC. It’s a sign that the chassis has been (quite literally) stretched to its limit.

  11. Great articles. A couple of clarifications:

    – For a motorhome it’s an OCCC sticker, Occupant and Cargo Carrying Capacity. It’s on the entry door frame usually.

    – Many people are under the impression that GVWR is solely while towing. While that is what the regs address, the same axles need to support the weight of the people inside once a trailer is parked. If the CCC is low on a trailer you can easily overload the axle(s) and frame while parked once you put your family of four inside.

    – The CCC and OCCC are not calculated; they must be determined by actually weighing the RV before it leaves the factory. Options can make a huge difference in the CCC/OCCC availability if heavy options are added.

    – When looking at RV’s, always take a pic of the sticker.

    • JJ, thanks for adding such excellent information! Just a point of clarification that CCC/OCCC is allowed to be calculated based on “representative equipment,” I believe. Not all manufacturers individually weigh each RV before it leaves the factory. Obviously, weighing individual units is by far the superior practice!

  12. My Sequoia 5.7 V8 is rated at 7300# tow capacity. I tow a Rockwood MiniLite 2109s. Sticker unloaded weight is about 4313#. Just my wife and I in the rig, not F/T…just trips. Loaded for a trip, the trailer weighs about 5800 with full water tank…that’s 100% of its allowable GVWR.
    733# tongue weight. But with my wife and I in the Sequoia, with the usual basic stuff we carry, plus that tongue weight, it weighs about 7100#…which is 100% of its allowable GVWR.
    Yet, the GCVWR (combined weight rating) is 91% of the sticker GCVWR. But really, I’m maxed out. That “4313#” trailer is really all my “7300” tow capacity TV can LEGALLY handle by the numbers…. BTW, it tows GREAT…been all over the USA with it. Blue Ox SwayPro hitch.

  13. Interesting article, thank you very much. I’m still a bit confused as to what is and is not included in the ‘unloaded’ vehicle weight. You say the propane IS included but the water in the freshwater tank is NOT included? Is it possible that those rules are not the same in Canada? I made an inquiry about a year ago to Alliance RV and was told the label on the side of the trailer was different because I was in Canada. Can you comment?

    • Gord, that is correct. However, US and Canadian manufacturers are getting closer to adopting universal standards … in the meantime, most US manufacturers now have a separate English/French Cargo Capacity sticker for Canadian compliance.

  14. Very helpful information! Thank you! Did the math and our 2022 New Aire 3545 CCC (Net Cargo Capacity per Newmar) is 14.5% of the GVWR (5600÷38600). We downsized to the New Aire and this is a great reminder that our pile of stuff we put into the RV also must be downsized. Thank you!

  15. Ross, thank you for this article. I have written here on RVTravel about the issues I have with the gas motor coaches built on the Ford F53 chassis. After upgrading springs and shocks, what I discovered is that the only way I can have a reasonably safe and stable ride is by lowering tire pressure (following tire mfg table). And it’s still not great! By taking features out of my Newmar 40′ Canyon Star toy hauler (the folding benches in the garage) and limiting cargo, I was able to reduce my tire pressures. Quite frankly, IMHO it is criminal the way the manufacturers load the chassis with solid wooden cabinets and trim and frankly ignore the problems weight creates.

    • Karel, you might be giving manufacturers too much credit! I think OSB and particleboard are the bigger culprits in most RVs than solid wood 😉 But I agree that what sells residential homes – marble, granite, hardwood – shouldn’t be the same measuring stick for RV construction. It’s a terrible weight penalty.

  16. One of (the many) reasons we decided on our 5th wheel was the cargo carrying capacity, It has tandem 7000# axles that match the GVWR. With an UVW of 11,400#, stated CCC on the label is 2600#. Pin weight is just under 2000# leaving 9400# resting on the 14,000# combined axles. Our new-to-us 2016 5th wheel was built on a HD 12″ frame and I went from F to G rated tires (replacing the Chinabombs) for added assurance. We live out of our 5th wheel 7-8 months each year and fill the cabinets, basement, and center bunkroom (converted to a box room) with a little over 2000#. And I tow the 5th wheel with a 1 ton HD diesel dually with 5300# CCC (roughly 2500# margin after subtracting the pin weight, supplies, passengers…). When I tow the 5th wheel, the truck rides like a limo and takes 8-10% grades like a champ, exhaust braking coming back down only briefly touching the brakes. So yes, do your homework before making those purchases. It requires several months of research followed by long search.

    • Oh, don’t listen to the showroom sales person. They only want your money and could care less whether you’re overloaded when you leave the lot.

  17. Our ’96 Flair comes in at 13,051 pounds (including me and the wife). That leaves us with 3,450 pounds fay under or water, waste tanks, or son and our food. We don’t have a toad, so we stay under weight. Glad we have the old class-a, with a decent weight rating.

  18. Excellent article!
    When I went RV shopping, I wanted more than needed CCC. I looked at several 5th wheels that had less than 2,000 lbs CCC; YIKES! I settled on a more expensive 35′ Montana that has 4,000 CCC. After several add ons such as 4 x AGM batteries, washer dryer combo, water required when traveling, etc. we travel with a maximum of 2,500 CCC. Just my two cents.

  19. The problem I have is there are no local scales available to the public for the purpose of weighing an RV trailer. And by local, I mean within 100+ miles. What am I going to a long way from home? Set up a roadside yard sale for the excess weight?

    Fortunately, I am hauling a small single axle travel trailer. I cannot easily get an axle weight for the loaded trailer, but I CAN obtain a tongue weight with a stout wood frame and a relatively inexpensive crane scale rated for half a ton. I raise the tongue above level, place a S-hook under the coupler at level and lower the coupler until the hitch is suspended on the scale with the tongue jack just above the ground. Assuming that I have properly loaded the trailer, I should be able to determine if I am within the GVWR using the tongue weight.

    The manufacturer specifies the UVW at 2,996, the GVWR at 3,850 and the maximum tongue weight at 350. So between 9%-12% of the trailer weight. So long as I am in that range I should be good.

    • No gravel pits, blacktop plants in your area? I worked in a quarry and if we had time we could weigh you and even do individual wheels . No charge but we usually had plenty of beer at the end of the day. No CAT 🐱 scales? I can think of 3 within 20 miles.

    • I have no idea where you live, but if there is a feed store that sells bulk feed, they can weigh you. That is where I go every single time I load up my trailer. Sometimes I take more, sometimes I take less, but I always do it to make sure my tongue weight & CCC is accurate for my rigs.

    • Jim, while I credit your ingenuity, using tongue weight to estimate GVW by assuming tongue weight percentage isn’t safe. As others have pointed out, many private businesses, such as iron and steel yards, should have platform scales accurate to ~40 lbs or so.

  20. Interestingly, the CCC sticker shown at the top of this article contradicts the article. It states that the CCC is after a full tank of water (and fuel) but with empty waste tanks.

    • Hello Rip! I’ll ask to have that changed … that shows a Canadian compliance label, which is not governed by FMVSS regulations.

  21. Looking at the small motorhome arena, inadequate OCCC is a plague. Snob appeal drives usage of the Sprinter chassis and “upscale” manufacturers like Tiffin and Airstream fill it with solid wood cabinets, leaving absurdly low capacities. Airstream manual says to never drive the Atlas (B+) with more than a 1/3rd full water tank! Tiffin Wayfarer this year even has a washer/dryer option in a 25 foot coach. Many lower end manufacturers, like Thor and Coachmen, use an E350 chassis where an E450 (+2k pound increase) would be much better for only about a 3k price increase. Thor Axis 24.1, for example, sleeps 5 people yet has an OCCC of about 1200 pounds.I expect that on any given day there are thousand of overloaded motorhomes on the road.

  22. If either axle exceeds the GAWR then either shift “stuff” to the other axle or unload enough “stuff” from the axle so as not to exceed the GAWR.

  23. I’m old school. CCC, UVW, NCC…mumbo jumbo. I prefer GVWR/GVW, GAWR/GAW, base weight, wet weight, payload, rolling weight.

    the advice I was given when we first began RVing in class A gas motor homes (1986) was to fill the fuel & LP tanks and then take the otherwise empty
    MH to a certified scale and obtain individual axle weights. that’s Base Weight and it should be significantly less than the Gross Axle Weight Rating for the axle. Be sure to subtract the driver’s weight from the base weight of the front axle.

    Next, fill the fresh water tank and re-weigh, again separate axle weights. That’s Wet Weight. The difference between the Gross Axle Weight rating and the wet weight of the axle is Payload. Payload is how much “stuff”…food, clothing, supplies, pets, tools and people can be safely carried.

    Finally, load the MH as you would for a trip. Everything. Don’t forget people and pets. Re-weigh (separate axle weights again). (contd)

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