Caravan & Trailer Weight FAQs
GVM or GTM is the total weight of a vehicle or trailer, including its empty weight (curb weight) and any passengers or cargo and extra added assesories
GVM or GTM = Curb Weight + Payload Capacity
Kerb weight is the weight of a vehicle or trailer when it is empty, with no passengers or cargo on board. This is also known as the unladen weight.
Kerb Weight = Total Vehicle Weight – Payload Capacity
Aggregate Trailer Mass (ATM) refers to the total maximum weight that a trailer is allowed to have when fully loaded. This is UNhitched from the tow vehicle
ATM = Tare Mass (Empty Weight of Trailer) + Maximum Payload Capacity
Gross Trailer Mass (GTM) is the maximum weight that a fully loaded trailer can have, including its own weight and cargo. This is when the trailer/caravan is Hitched to the tow vehicle
GTM = Curb Weight of the Trailer + Payload when in transit
Payload is the maximum weight of passengers, cargo and accessories (extra water tanks, extra solar, etc on your caravan or bullbars, roofracks, canopys etc, of vehicle) that a caravan or tow vehicle can safely carry in addition to its curb weight.
GVM – Kerb Weight = Payload
Eg. Isuzu Dmax
Kerb weight (2115) – GVM (3100) = Payload 985kgs²
Gross Axle Weight Rating (GAWR) is the maximum weight a single axle of a vehicle or trailer can safely support.
GCM is the maximum combined weight of the tow vehicle and the trailer/caravan, including all passengers, cargo, and GTM of the trailer. It represents the total weight that the vehicle and trailer can handle safely when combined.
GCM = (GVM) Gross Vehicle Mass + (GTM) Gross Trailer Mass
Tow ball weight is the downward force put on the hitch of the tow vehicle by the trailer’s tongue or hitch (do35 or 50mm-70mm coupling). It’s an essential factor in maintaining stability while towing.
Tow ball Weight = 6% to 10% of ATM
Eg. if your ATM is 3000 your towball weight should be no more that 300kg
The axle weight is the weight supported by a single axle on a vehicle or trailer.
GTAWR is the maximum weight a trailer’s axles are rated to support. It helps ensure that the trailer can safely carry its load.
This number should be the same or higher than the Caravans ATM & GTM
UVW, or Unloaded Vehicle Weight, represents the weight of a vehicle or trailer when it comes from the factory with standard equipment and fluids but without additional cargo, fuel, or personal items.