GVM - Gross Vehicle Mass

This is the maximum your car can weigh including all passengers, pay load, accessories. It also includes the tow ball mass when towing.

GCM - Gross Combination Mass

This is the maximum your car and trailer can weigh hitched together travelling down the road fully loaded.

GTM - Gross Trailer Mass

This is the maximum allowed weight of trailer/caravan measured at the wheels while connected to the tow vehicle.

ATM - Aggregate Trailer Mass

This is the maximum weight of trailer/caravan while disconnected from the tow vehicle.

TBM - Tow Ball Mass

This is the weight applied to the tow hitch of the vehicle by a trailer/caravan. It must be included when measuring the GVM of any tow vehicle.