Saturday, June 3, 2023


Check the specs before buying an RV

By Dave Helgeson

There is a saying that goes something like this: “Ain’t she pretty, ain’t she fine, I am going to make her mine.” Unfortunately the decision to buy an RV is often based on looks (curb appeal – inside and out) rather than function. Yes, buyers consider floor plan and amenities in their buying decision, but many fail to take a close look at specifications until after the sale – often discovering the unit doesn’t fit their planned uses for it.

Some items to look for in an RV:

  • Cargo Carrying Capacity (CCC): The CCC is the weight of items the RV can safely carry without becoming overloaded. For the past ten years or so RV manufacturers have been required to post the CCC on the RV, but unfortunately few feel obligated to include the CCC in brochures or on the specifications listed on their websites. Following is how to calculate CCC if you are looking to purchase an older RV that does not include a CCC sticker or you need to calculate it for a new unit based on the basic information you are able obtain from the manufacturer.

The Cargo Carrying Capacity (CCC) of an RV can be calculated by taking the Gross Vehicle Weight Rating (GVWR) then subtracting the dry weight of the RV, the weight of the full water tank, the weight of full propane tanks and the seating capacity weight rating (SCWR). Detailed instructions:

  1. Find the vehicle’s gross vehicle weight rating (GVWR) on manufacturer’s specifications.
  2. Subtract the vehicle’s dry weight aka unloaded vehicle weight (UVW).
  3. Subtract the weight of the fresh water (water tank and water heater) the unit is designed to carry. Note: Water weighs just over 8.3 pounds per gallon.
  4. Subtract the weight of propane the vehicle can carry. Note: Propane weighs just over 4.2 pounds per gallon
  5. If the RV is a motorhome, subtract the weight of the seating capacity weight rating (SCWR) (150 pounds times the number of seating positions).

Note: Options or accessories added by the manufacturer, dealer or yourself also need to be subtracted from the CCC as they are not included in the base empty weight of the unit.

A  low CCC might not be a problem for a couple using the RV on short trips where they are carrying minimal food, gear, etc., traveling to a full hookup RV park. That would negate the need to travel with a full potable water tank and returning home with full holding tanks. However, a low CCC will most certainly be a problem if you are looking to live full time in the RV taking all of your worldly possessions with you. Click here to learn more about dreaded low Cargo Carrying Capacities and some options to counter them from RVTravel’s own Russ and Tiña De Maris.

  • Towing Capacity: If you are looking to purchase a motorhome and plan on towing a dinghy, boat, cargo trailer, etc., be sure and check what the unit is rated to tow before completing the purchase. You will need to check the towing capacity of the drive train as well as carrying capacity (both total weight and tongue weight) of the hitch.
  • Tank Capacities: I am not sure manufactures ever place much thought into tank capacities (potable fresh water, grey and black tanks) other than what will conveniently fit in the remaining space after everything else in the unit has been laid out. Maybe they think everyone stays in a full-hookup RV park and tank capacities don’t really matter.

You will typically find one of the following two scenarios: 1) A large fresh water tank and insufficient black and grey tanks to handle the downstream side of the equation, leaving you wondering how you could ever use all of your fresh water before overflowing  your waste tanks. 2) A modest-sized fresh water tank and huge holding tanks, leaving you wondering in what situation could you ever utilize the full capacity of the waste tanks.

There are plausible answers to both scenarios, but they don’t apply to the average RVer, so be sure to review the specifications and make sure the capacities are in line with how you plan to use the RV.

While buying an RV is an exciting experience, slow down and take a moment to “check the specs” – making sure the unit is right for you and your RV lifestyle to avoid disappointment down the road.


Dave Helgeson
Dave Helgeson
Dave Helgeson has been around travel trailers his entire life. His grandparents and father owned an RV dealership long before the term “RV” had been coined. He has served in every position of an RV dealership with the exception of bookkeeping. Dave served as President of a local chapter of the RVDA (Recreational Vehicle Dealers Association), was on the board of advisors for the RV Technician Program of a local technical college and was a board member of the Manufactured Home and RV Association. He and his wife Cheri operated their own RV dealership for many years and for the past 29 years have managed RV shows. Dave presents seminars at RV shows across the country and was referred to as "The foremost expert on boondocking" by the late Gary Bunzer, "The RV Doctor". Dave and his wife are currently on their fifth travel trailer with Dave doing all the service, repair and modifications on his own unit.


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1 year ago

Every Rv should have a big sign at the door – “Check the Specs!”. I have a lot of storage “space” – but all I can carry is feathers in our 34 ft. Class A. The front axle is almost over GAWR from the factory before I get my 152 lbs in the seat! Adding water to the tank at the very back helps relieve some weight off the front but that reduces the overall weight capacity. (I usually carry only about 10 gals of water in that tank). So, YES by all means check the specs and weigh everything you put in – you will be amazed at how much a few clothes and can goods weigh! (I also have a 78 gal. gas tank just aft of the rear axle – grat range a 7.5 to 9.0 mpg – but! ). Oh, by the way – get it weighed and analyze the balance of where the weight is! “Weight and balance check before takeoff”.

1 year ago

Buyers should also look at weight distribution in the design. There will be no specific info given a buyer on this except axle weight ratings on motor homes.

I experienced this personally in 1999 when we purchased our first class A…a Fleetwood Bounder. We had looked at…even studied…many specs, but it never dawned on me to think about how those potentially heavy items, like water and fuel and waste tanks were laid out. On our unit there was a 100 gallon water tank WAY at the back. Also behind or just over the rear wheels was the 75 gallon gas tank, the grey and black water tanks, and the onan generator!

I finally got smart enough to think about weight distribution and did the calculations…then ran it on a scale. I found we were about a half ton over on the rear axle. Plenty of extra capacity on the front axle, but no way to shift all that weight forward.

Lesson: Don’t count on an RV engineer/designer to do weight distribution correctly!

Bob M
1 year ago

I always check the tank capacity to make sure they are adequate. I liked a couple of those retro travel trailers. But their tank capacities were too small, especially the black tanks.

Michael Gardner
1 year ago

Another “hidden number” is tongue weight on a trailer. They estimate it for you, but the build of the unit has a major effect. Our TT had the fresh tank forward of the axles, and if we filled the tank before heading out to boondocks, tongue weight “estimated” at “around 700” was actually 1100.

Bill Massicotte
2 years ago

I have the Coachmen Pursuit 30FW and we have plenty of room and storage space. We even bring our breadmaker, blender (for margaritas), instant pot, toaster etc…
The 75 gallon fuel tank takes us a long ways with the new and improved V-10 and 6-speed tranny. We spend the Winter in New Mexico and have no shortage of space or room for clothing. The ride is a little harsh but I am working on it. Just changed out the headlights for better night vision. We think the rig is adequate for our needs. Not suited for full-timing in our opinion.

Dennis G
2 years ago

Just ran the math on our old ’96 RV. Our GVWR is 14,800 and have a CCC of 2,404. I feel so lucky now.

2 years ago

The Jayco mentioned has the smallest tanks I’ve ever heard of (except for a pop up, maybe…and a lot of those don’t have waste tanks at all).

2 years ago

You might also add that if you plan to live full time in your RV you need to consider the 3 C’s for storage. Closet space, cabinet space and Counter space. I once bought a beautiful Bighorn Fifth wheel that was perfect for vacationing in but had to trade it in for something more livable.

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