How to load a caravan safely

Where heavy gear goes, what full water tanks do to your tow ball, why drawbar boxes and bumper racks cause trouble, and why you weigh after packing.

Facts checked 25 Sep 2026

Start with how much you can carry

A caravan's payload is its ATM less what it actually weighs empty (see ATM vs GTM). RACQ puts it at less than 400 kg for many caravans. Weigh the empty van rather than trusting the tare on the plate, because accessories and modifications add weight.

Water and waste tanks are not part of a caravan's tare. Tare is measured with them empty, so every litre you carry is load.

It goes quickly. In Transport for NSW's worked example, a van with 400 kg to spare is 58 kg over at 458 kg, from a packing list that looks modest and includes 100 L of water. Payload has the full example.

Heavy items low, over or just ahead of the axles

Once you know how much you can carry, where it goes matters as much. The heaviest items go low, centred over and close to the caravan's axles. The lightest go up high. Packed that way, the van is less prone to snaking and sway.

Put most of the weight over the axles, then toward the front of the van, and the least at the rear.

That order matters. A caravan rests on its axles at one end and on your tow ball at the other. Weight just ahead of the axles adds a little to the tow ball. Weight behind them takes mass off the tow ball and makes the van's back end heavy. It is the same lever model explained in front and rear axle limits, and it is why the front of the van comes ahead of the rear.

Balance side to side too, and load the van evenly on both sides. Some vans are heavier on one side because of where the fridge or stove sits, so load portable gear on the other side. Once you find a loading pattern that tows well, repeat it every trip.

The drawbar and the rear bumper

The two ends of a caravan are the worst places for weight: they sit at the two ends of the lever above. Keep heavy items off the front and rear extremities, such as drawbar storage boxes, the rear bumper bar, large toolboxes and motorcycle racks. Heavy items behind the rear axle can significantly increase the potential for sway.

Drawbar. Gas bottles, toolboxes and jerry cans here load the tow ball almost directly. VSB1 also says the drawbar must not be modified from how it was tested to carry extra load without another drawbar test.
Rear bumper and racks. Bikes, spare wheels and boxes behind the axles do what any weight behind them does, as above: take mass off the tow ball and add it to the van's back end. There is a second limit too: anything on the back still has to keep the rig within the length and rear overhang limits (see state towing rules).

VSB1 counts these fittings as load. A caravan's allowance for jerry can holders has to include the jerry cans and their fuel, and a bike rack's allowance has to include the bikes.

Water tanks and gas

Water is the heaviest thing most people carry, and, as above, none of it is in the tare: every litre is 1 kg, before you count the tank itself. Gas is the other one people underestimate: a "9 kg" cylinder holds 9 kg of gas, and a steel cylinder weighs roughly the same again empty, so a full one is about 18 kg.

Water in the tanks can increase tow ball mass. Whether it goes up or down depends on where the tank sits, by the same lever as any other load: a tank ahead of the axles adds to the tow ball as it fills, and one behind them takes weight off. Know where yours are, and weigh the van with the tanks as you actually travel.

Tanks fill in other ways too. Grey water, the toilet cassette and things you pick up along the way add weight during the trip.

The simplest saving is to carry less. Don't carry large quantities of water unless there is none where you are going. Fill tanks and buy supplies at your destination, and drain the tanks before moving on.

Tow ball mass: guides vary, your limit does not

Everything above, from where the heavy items sit to how full the tanks are, sets your tow ball mass. The published guides differ: the NSW Government gives about 5–10% of the trailer's loaded mass, and the WA Department of Transport 8–10% of ATM. The motoring associations offer similar rules of thumb: RACQ's is not to exceed 10% of ATM unless otherwise indicated, and RAC WA's is about 10% of the trailer's weight. Tow ball mass compares the guides in full.

The hard limits are the ones on your vehicle and towbar. The WA Department of Transport says the download must not exceed the maximum for the vehicle and towbar, and that too much or too little reduces stability. RACQ suggests aiming between 50% and 100% of the vehicle's maximum. Don't simply move gear to the back of the van to bring the ball load down: as above, weight behind the axles hurts stability.

A weight distribution hitch is not the fix for a badly loaded van. The WA Department of Transport and the Queensland Government both say so.

What goes in the tow vehicle

The car has its own limits, and the caravan's load does not stay in the caravan:

Tow ball mass counts toward the vehicle's GVM. See GVM.
Everything counts toward GCM. The WA guide's example: a vehicle with a 2,740 kg GVM and a 4,600 kg GCM, towing a 2,250 kg trailer. Load both to the maximum and the combination is 4,990 kg, well over the GCM. See GCM.
Count the vehicle's extras. Passengers, tools, camping gear, bull bars, long-range fuel tanks, extra batteries and roof racks all add up.
Watch the rear axle. A vehicle can be under GVM and still over on its rear axle, and nearly all of a dual-cab ute's load space is behind the rear axle. It is the same lever as in the van, with the rear axle as the pivot (see front and rear axle limits).

The caravan's luggage is separate from the tow vehicle's, just as the van's payload is separate from the vehicle's (see payload). Neither has room to take the other's overflow unless both sets of limits allow it.

Secure everything

Secure all loads so nothing loose can move while driving. Don't leave loose items on the floor, secure cupboards and tape down anything that could shift. Loads must be secured under the road rules too; the NSW Government and the WA Road Safety Commission both say so.

Weigh after you pack

Everything above is packing guidance, and it only gets you close. Have the caravan weighed once it is loaded, and reweigh after any significant change in what you carry or where you carry it. Weigh again each time you make a modification that adds weight. See how to weigh your rig.

Common questions

Should I travel with full water tanks?

Only if you need the water. As above, don't carry large quantities unless water is unavailable at your destination. Whatever you decide, weigh the van the way you actually travel, because water changes both the total and the tow ball mass.

Is it OK to put a toolbox on the drawbar?

As covered above, it adds almost directly to your tow ball mass, and a drawbar box is one of the places heavy weight should not go. VSB1 also says a drawbar must not be modified to carry extra load without another drawbar test.

Where should I put heavy items in a caravan?

Low, and over or just ahead of the axles, for the lever reasons above.

Why does my caravan sway after I added a bike rack?

It is the rear-bumper problem above. Weight behind the axles takes mass off the tow ball and makes the rear of the van heavy, and heavy items behind the rear axle can significantly increase the potential for sway.

Sources

Authorities

Motoring associations (advice)