Somewhere on every vehicle out there, you can find a label that includes specific data on the vehicle itself, including the VIN (Vehicle Identification Number), the vehicle’s Curb Weight, and its GVWR number.

Every towing vehicle and trailer should have a GVWR, or Gross Vehicle Weight Rating, written on it. GVWR is the legal maximum gross weight of this vehicle and its contents, essentially passengers, and all of its cargo (but not of a vehicle it is towing).

You need this number in order to calculate what you can safely and legally carry and tow. Typically it’s seen as a maximum, but the vehicle owner who travels in hilly country or mountains should take care to give themselves plenty of margin for a more enjoyable and safe trip.

How Things Work has a more detailed discussion of GVWR.

Gross Vehicle Weight is the weight at any given time of a vehicle and its contents. It changes when people and things go in or out of the vehicle. In contrast, the GVWR (the rating) never changes.

Curb Weight is what a vehicle weighs sitting at a curb, with little or nothing in it: some say only a driver weighing 150 pounds, others say a full tank of gas and other fluids needed to operate the vehicle.

GCWR, a characteristic of the towing vehicle, stands for the Gross Combined Weight Rating: the maximum allowed weight of a vehicle and its cargo including a trailer or camper and its contents.

GTWR, a characteristic of a trailer, is Gross Trailer Weight Rating, the maximum allowed weight of a trailer, by itself, and its various contents. Note that sometimes camper manufacturers will use GVWR or GTWR for a camper to indicate the empty weight of the camper.

GAWR stands for Gross Axle Weight Rating. GAWR is the maximum allowable weight on an individual axle of a vehicle or camper.

See also the National Highway Traffic Safety Association on how to use the towing ratings of a vehicle.

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