At A&L Mobile weighing Services, we provide accurate, mobile weighing services across Port Stephens, Newcastle, Maitland, the Hunter Region, Upper Hunter, and Central Coast NSW. We help you stay safe, compliant, and insured by ensuring your vehicle and towing setup are within legal weight limits.
According to NSW transport statistics, more than 40% of caravans and trailers on the road are overweight. This is often due to a lack of understanding of GVM, GCM, ATM, and payload limits. Many vehicle and caravan owners fail to factor in everything they carry—tools, water, fuel, gear, food, accessories—resulting in dangerous and illegal setups.
Overloaded vehicles can:
Put lives at risk (your family and others on the road)
Cause poor handling and braking
Lead to mechanical failure
Void your insurance as your setup may be deemed unroadworthy
Don’t delay your weigh, Book with A&L today! Let us help you tow safely and legally
At A&L Mobile Weighing Services, we’re here to make sure you understand the key vehicle and trailer weights that impact towing safety, compliance, and insurance. Whether you’re new to caravanning or upgrading your 4WD setup, knowing your weight limits is essential to avoid overloading and fines—and to keep you and your family safe on the road.
Below is a simple guide to help you understand the key terms and how they affect your towing setup:
The Tare Mass of your vehicle is its weight at manufacturer specification, including necessary operating fluids (fuel, oil, coolant), but excluding any passengers, cargo, or aftermarket accessories.
The Tare Mass of your caravan is its weight as supplied by the manufacturer, empty and without any added load, but including standard fixtures.
The ATM is the maximum allowable weight of your fully loaded caravan, including water, gas, food, camping gear, and any added accessories.
ATM = Tare Mass (caravan) + Maximum Payload
❗ The ATM is a legally set limit by the manufacturer and must not be exceeded.
The GVM is the maximum weight your tow vehicle can legally carry, including its own weight, passengers, luggage, and the tow ball mass when hitched.
GVM = Vehicle Tare Mass + Payload (including TBM)
Your vehicle’s Payload includes anything added to the vehicle after manufacture, such as passengers, luggage, bull bars, roof racks, tools, and the tow ball mass from the trailer.
Payload does not include fuel, oil, or coolant.
This is the maximum weight you’re allowed to load into the caravan, such as:
Water tanks
Gas bottles
Camping gear
Aftermarket accessories
Maximum Payload = ATM – Tare Mass (caravan) – TBM
Tow Ball Mass is the downward force your caravan applies to the tow vehicle’s tow ball when fully loaded. TBM counts towards the vehicle’s GVM, and is a key consideration in safe towing balance.
The GTM is the maximum weight of your loaded caravan that is supported by its own wheels, not including the portion carried by your tow vehicle via the tow ball.
GTM = ATM – TBM
GCM is the total allowable mass of the fully loaded vehicle and fully loaded caravan/trailer. It’s the combined limit set by the vehicle manufacturer.
GCM = GVM + GTM
❗ This is one of the most critical limits to check when towing. Exceeding your GCM can void your insurance and cause serious safety issues.
Most weight ratings, including Tare, ATM, TBM, and GTM, are found on your vehicle or caravan’s VIN plate or compliance plate. If you’re unsure how to interpret them, our mobile weighing service can help you decode everything clearly.
We provide a comprehensive weight report, explain each component, and give practical recommendations so you can:
Avoid fines and insurance issues
Tow safely and legally
Plan future upgrades confidently
Tow with total peace of mind.
Serving Port Stephens, Newcastle, Central Coast, Hunter Valley, Upper Hunter, and beyond.
