In 1996, the Recreational Vehicle Industry Association (RVIA) established a list a list of weight ratings that manufacturers had to post inside every RV they made. In 2000, they added a few more ratings to the list to help RV owners. In 2008, all those were superseded by new regulations adopted by the National Highway Traffic Safety Administration that mandated separate and specific RV weight labels. That means the list on your RV may very well be different from another RV produced in another year.
Cargo Carrying Capacity (CCC) - The CCC is the GVWR minus the UVW, the SCWR, the weight of a full tank of propane, and the weight of all fresh water in the system including a full fresh water tank and a full water heater.
Curb Weight - The weight of a basic RV unit without fresh or waste water in the holding tanks but with automotive fluids such as fuel, oil, and radiator coolant.
NCC (Net Carrying
Capacity) – is the maximum weight of all passengers (if applicable),
personal belongings, food, fresh water, supplies -- derived by subtracting the
UVW from the GVWR. In 2000, the RVIA started using Cargo Carrying Capacity (CCC) and added a sleeping capacity weight rating
GAWR (Gross Axle Weight Rating) - The manufacturer's rating for the maximum allowable weight that an axle assembly is designed to carry. Gawr applies to tow vehicle, trailer, and fifth-wheel and motor home axles.
GCWR (Gross Combination Weight Rating) – is the maximum allowable weight of the combination of tow vehicle and trailer/ fifth-wheel, or motor home and dinghy. It includes the weight of the vehicle, trailer/fifth-wheel (or dinghy), cargo, passengers and a full load of fluids (fresh water, propane, fuel, etc.).
GVWR (Gross Vehicle Weight Rating) — how much weight a vehicle is
designed to carry, set by the manufacturer. The GVWR is typically listed on a
data plate near the driver’s doorframe, and includes the net weight of the
vehicle, plus the weight of passengers, fuel, cargo and any additional accessories.It assumes that the towed vehicle will have its own braking system. This why motorhome owners shouldn't tow a vehicle without a supplemental braking system.
GTWR (Gross Trailer Weight Rating) - Maximum allowable weight of a trailer, fully loaded with cargo and fluids.
Hitch Rating - Stamped into the hitch receiver or a placard attached to the rear of a motorhome. The number includes the maximum trailer or towed vehicle weight as well as the tongue weight on the hitch.
Hitch Weight - The amount of weight imposed on the hitch when the trailer/fifth-wheel is coupled. Sometimes it is referred to as conventional trailer "tongue weight." Hitch weight for a travel trailer can be 10-15 percent of overall weight; fifth-wheel hitch weight is usually 18 to 20 percent of the overall weight.
NCC (Net Carrying Capacity) – added in 1996, it is the maximum weight of all passengers (if applicable), personal belongings, food, fresh water, supplies -- derived by subtracting the UVW from the GVWR.
Occupant and Cargo Carrying Capacity (OCCC) - The CCC was modified in 2008. CCC still applies to towable RV's but motorized RV's use the OCCC. It is calculated by taking the GVWR and subtracting the UVW and propane weight. It is the maximum allowable weight of all occupants including the driver plus the weight of all food, tools, fresh water tanks, full propane tanks, and all personal belongings.
Payload Capacity - The maximum allowable weight that can be placed in or on a vehicle, including cargo, passengers, fluids and fifth-wheel or conventional hitch loads.
Sleeping Capacity Weight Rating (SCWR)- is calculated by multiplying the number of sleeping positions by 154 pounds.
Tongue Weight - The amount of weight imposed on the hitch when the trailer is coupled.
Tow Rating - The manufacturer's rating of the maximum weight limit that can safely be towed by a particular vehicle. Tow ratings are related to overall trailer weight, not trailer size, in most cases. However, some tow ratings impose limits as to frontal area of the trailer and overall length. The vehicle manufacturer according to several criteria, including engine size, transmission, axle ratio, brakes, chassis, cooling systems and other special equipment, determines tow ratings.
UVW - (Unloaded Vehicle Weight) - New in 1996, this is the weight of the vehicle as delivered with full fuel, oil, and coolant, but without manufacturer's or dealer-installed options and before adding passengers, driver, propane, or fresh water.
Weights - water (weight): 8.3 lbs. per gallon; LP gas (weight): 4.5 lbs. per gallon; Gasoline: weighs 6.3 pounds per gallon; Diesel fuel: weighs 6.6 pounds per gallon; Propane: weighs 4.25 pounds per gallon.
Wet Weight - Term used by RVers to describe the weight of a RV with all storage and holding tanks full. i.e., water, propane, etc.