The Caravan Glossary
Every Term Explained

Also called absorbent glass mat.

A sealed lead-acid battery type that costs less up front and is heavier for the power it gives. As a rule of thumb only about half its rated capacity is usable charge before you start shortening its life.

Also called agreed value, market value.

Two ways an insurer can settle a total loss. Agreed value fixes the payout figure when the policy is taken out, while market value pays what the van is judged to be worth at the time of the claim.

Also called stucco aluminium.

Sheet aluminium with a dimpled stucco finish, wrapped over a frame. It is the traditional Australian caravan skin, light and repairable sheet by sheet, and you can pick it by the ripple in the surface.

Also called awning walls.

A canvas or vinyl room that attaches to the van's awning to give you a second living space at camp. A full annexe walls in the whole awning, while a lighter privacy screen closes off part of it.

Also called Aggregate Trailer Mass.

ATM is the most your caravan is allowed to weigh when it is fully loaded and standing on its own wheels, unhitched from the car. The manufacturer sets it and it is stamped on the van's compliance plate. Your loaded van must never go over it, however strong the tow car is.

Also called tow ball mass, tow ball download, TBM.

Ball weight is the downward force the van's coupling puts on your tow ball, commonly quoted as around 8 to 12 per cent of the loaded van. It is carried by the car, so it comes out of the car's payload rather than the van's. Too little of it and the van sways, too much and you overload the car's rear axle.

Also called residual.

A lump sum left owing at the end of a loan term instead of being paid off across the regular repayments. It lowers the repayment along the way and leaves an amount to be paid, refinanced or covered by selling the van when the term ends.

Also called amp hours, Ah.

How much charge the van's batteries hold, quoted in amp hours. More amp hours means longer running the fridge, lights and water pump between charges, and how much of that figure you can actually use depends on the battery type.

Also called cassette toilet, chemical toilet.

The waste from the toilet. Most Australian vans use a cassette, a removable tank you carry to a dump point, rather than a fixed black water tank underneath.

The unit in the tow car that tells the van's electric brakes how hard to work. A proportional controller reads how hard the car is braking and matches it, while a time-delayed one ramps up on a fixed curve. Some cars come with one built in from the factory.

The heaviest trailer with its own brakes that your car's manufacturer allows it to tow. It is a ceiling rather than a promise: GCM, GVM, the ball weight limit and the towbar's own rating all apply at the same time, and the lowest number wins.

Also called breakaway system.

A safety cable running from the van to the car, separate from the coupling. If the van ever comes off, the cable pulls a switch that applies the van's own brakes instead of letting it run free. Australian rules make one compulsory on trailers over 2 tonnes, and the small battery that powers it has to be charged to be any use.

Also called lead time, factory order.

The place your ordered van holds in the factory queue, and the wait before it is built. It is the difference between buying a van off the floor today and ordering one built to your own spec.

Also called family van, bunks.

A layout with fixed bunks, usually two or three stacked at the rear, built for travelling with kids. Bunks add weight and take the space an ensuite or a club lounge would otherwise use.

A light towable trailer that folds or pops out into a tent-style setup at camp. It tows and stores easily, and there is real setup work at each end of the day.

The steel frame the whole caravan is built on, running the length of the van and carrying the axles, the drawbar and the body. How big the rails are and how the steel is protected against rust are two of the things that separate a van built for bitumen from one built for gravel.

Also called chequer plate.

The patterned aluminium sheeting fitted low along the front and sides of a van. It takes the stone chips instead of the cladding, which is why vans built for gravel carry more of it.

Also called rear club lounge, U-shaped lounge.

A U-shaped lounge, usually across the back of the van, that uses the full width and normally folds down into a bed. It gives you a proper sitting room away from the bedroom, at the cost of making the bed up each night.

A single figure that folds an advertised interest rate together with the standard fees on a loan, so two offers can be lined up against each other. It is worked out on a set example, so the figure for your own loan will differ.

Also called VIN plate, build plate.

The metal plate fixed to the caravan, usually on the drawbar or inside the door frame, carrying its VIN and its legal weight limits including ATM and ball weight. Where the plate and the brochure disagree, the plate is the one that counts.

Also called sandwich panel, fibreglass composite.

Wall panels made as one bonded sheet, typically a foam core between two skins, with no separate frame inside. They are stiff and well insulated with no timber in them, and they are repaired as a whole panel rather than a sheet.

Also called hitch.

The mechanism that connects the van's drawbar to the tow ball or pin on the car. A standard 50mm ball coupling suits sealed roads, while vans built for rough country use a heavier articulating coupling that allows far more movement between car and van.

Also called DCDC charger.

A charger that takes power from the car's alternator while you drive and feeds it into the van's batteries at the right voltage. It is what turns a driving day into a charging day, and modern cars generally need one rather than a plain cable.

When the layers of a composite panel come unstuck from each other, usually showing up as a bubble or a soft spot in the wall. It is what buyers are pressing panels looking for on a used composite van.

The value a van loses over time, driven mostly by age, condition and how sought-after the model is. For most caravans it is the largest single cost of ownership.

Also called off-road hitch, articulating coupling.

A pin-style off-road coupling that lets the car and van twist and pivot independently on uneven ground, where a standard ball coupling would bind. You will hear the name used loosely for that whole style of hitch, alongside others such as McHitch.

Also called A-frame.

The two rails that run forward from the front of the van to the coupling, usually in an A shape. The gas bottles, the jockey wheel and often the stone guard sit on it, and on most vans so does the compliance plate.

Brakes on the caravan's own wheels, worked electrically from the tow car rather than leaving the car to stop everything. Any van heavy enough to be worth towing has them, which is why the car needs a brake controller.

Also called caravan stability control.

A unit fitted to the caravan that senses the start of sway and pulses the van's own brakes to pull it straight. It is a caravan-side system, separate from the stability control built into your car.

Also called internal bathroom.

A bathroom built into the van with a shower and toilet, so you are not walking to the amenities block. It is usually at the rear, and it costs you both floor space and payload.

Also called water tanks.

How many litres of clean water the van's tanks hold. Every litre weighs a kilogram, so filling big tanks can spend a large slice of your payload before a single bag goes in.

The storage box on the drawbar at the very front of the van, usually home to the generator, hoses and levelling ramps. Everything in it sits ahead of the axles, so it presses down on the tow ball and lifts your ball weight.

A caravan built for genuinely rough, unformed tracks, with a heavy-duty chassis, serious ground clearance and an articulating coupling. As with semi off-road, no Australian standard defines the label.

Also called Gross Combination Mass.

GCM is the most your loaded car and loaded caravan are allowed to weigh together, set by the car's manufacturer. It is the limit that catches experienced buyers, because many cars cannot sit at full GVM and tow their full rated weight at the same time.

A tank that holds the used water from your sink and shower until you can empty it at a dump point. Some parks and free camps expect you to carry one rather than let it run onto the ground.

Also called Gross Trailer Mass.

GTM is the weight sitting on the caravan's own axles when it is loaded and hitched to the car. It works out to ATM minus the ball weight, because once you hitch up the car carries part of the load.

Also called Gross Vehicle Mass.

GVM is the most your tow car is allowed to weigh fully loaded, counting passengers, fuel, luggage, accessories and the ball weight pressing down on the towbar. It is on the car's compliance plate. Hitch up a van with 250kg on the ball and you have just spent 250kg of the car's own carrying capacity.

Also called hot dip galv, galvanised chassis.

A rust protection method where the finished steel chassis is dipped in molten zinc, so the coating covers the steel inside and out, including the inside of the rails. That is a different thing from a painted or powder-coated chassis, which is protected on the outside only.

A compact hard-walled van sitting between a camper trailer and a full caravan. It is kept short and light enough to follow a 4WD into places a full van will not go, and the living space is smaller for it.

A setup where each wheel moves on its own arms and shock absorbers, instead of being tied to the wheel opposite through a solid axle and leaf springs. It rides better over rough ground and costs more, which is why it turns up mostly on vans built for dirt.

A device that turns the van's 12V battery power into 240V household power, so you can run things like a laptop charger or a TV away from a powered site. Anything with a heating element pulls hard on the battery through one.

The small wheel on a wind-up leg at the front of the drawbar. It holds the van level when it is unhitched and lets you push it around by hand.

Also called kerb mass.

Kerb weight is what your car weighs ready to drive, with a full tank of fuel and nobody in it. Take it off the car's GVM and what is left is the car's payload, which has to cover people, gear, accessories and the van's ball weight.

Also called LiFePO4, lithium iron phosphate.

A lighter battery chemistry, usually LiFePO4, that lets you safely use most of its rated capacity and recharges faster than lead-acid types. It costs more up front and weighs less for the same usable power.

A vehicle with the living area built in, so there is nothing to tow. The trade is that you pack up camp every time you want to drive somewhere.

Also called free camping, bush camping.

Camping where no power, water or dump point is supplied, so the van runs on its own batteries, solar and tanks. How many nights you get comes down to battery capacity, how much sun the panels catch, and how much water you can carry.

A caravan built for sealed roads and light gravel. It is typically the lightest and simplest style to tow, and it gives you the most living space for the weight.

Also called carrying capacity, load capacity.

Payload is everything you are allowed to add to the van: water, gas, food, bedding, tools, chairs and the annexe. It is ATM minus Tare. Water is what catches people out, because every litre you carry weighs a kilogram.

Also called pre-delivery inspection.

The check done before you take delivery of a new van, going over the electrics, plumbing, gas, seals and fit-out. Do your own alongside the dealer's, because anything found before you sign is far easier to have fixed than anything found after.

Also called price on application.

Price on application: no public price has been published for that van, so you have to ask for one. On our pages a range with no published price shows as POA rather than an estimate.

A caravan whose roof winds down for towing and lifts to full standing height once you are parked. It tows lower and fits more garages, and the trade is canvas in the raised section and less overhead cupboard space.

Also called Personal Property Securities Register, encumbrance check.

A search of the Personal Property Securities Register, run against the van's VIN, showing whether money is still owed on it or whether it has been written off or reported stolen. It is the standard check before handing money over for a used van.

A lender's indication of how much it is prepared to lend you, given before you have picked a van. It tells you the budget you are actually shopping with rather than the one you hope for.

Also called maximum caravan width, maximum caravan height.

Without a permit a caravan may be up to 2.5m wide and 4.3m high, measured to the outermost fixed point. Air conditioners, solar panels, awning rails and roof boxes all count towards it, so measure the van as it travels rather than trusting the body height on a spec sheet.

Also called runout stock, superseded stock.

Vans built to the previous model year that a dealer still has on the floor once the new model year has arrived. The van is finished and sitting there, which is usually where the sharper deals are found.

A loan where the item being bought is listed as security for the debt, so the lender holds a claim over it until the loan is paid out. It is the structure most caravan lending uses.

A caravan toughened for well-formed dirt roads and typical outback touring, with stronger suspension and more clearance than an on-road van. No Australian standard defines the label, so it is the maker's own description of its own product.

One axle with a wheel on each side. It keeps a van lighter, cheaper to maintain and easier to manoeuvre into a tight caravan park site.

The combined wattage of the solar panels on the roof, which sets how fast the battery refills on a good day. Shade, dust and the angle of the sun mean you rarely see the full rated figure.

A mesh or solid screen across the front of the van that catches stones thrown up by the car's tyres. It is there to protect the front window, the gas bottles and the cladding on gravel roads.

Also called snaking, yaw.

The side to side swinging of a van behind the car, which gets worse with speed and can start pulling the car with it. Too little ball weight, a tail-heavy load and the air off a passing truck are the usual triggers. The standard advice is to ease off the accelerator and let the rig slow itself rather than grabbing the car's brakes.

Two axles close together on each side, sharing the load across four wheels. It is what bigger vans use to carry more weight, and it tracks more steadily behind the car.

Also called tare mass.

Tare is the caravan's weight as it left the factory, with empty tanks, empty cupboards and nothing packed. It is the smallest weight on any spec sheet, and it is not a weight you will ever tow at.

Also called meranti frame.

A wall frame built from timber, usually meranti, with cladding fixed over it. It has been the standard method in Australia for decades and it is straightforward to repair, and it is the construction where keeping water out matters most.

The maximum towed weight and maximum ball weight the towbar itself is built for, shown on a plate on the bar. It is a separate number from the car's own rating, and your real limit is whichever of the two is lower.

A storage space running right through the van from one side to the other, so long items like fishing rods, camp chairs and awning poles slide in from either end.

The heaviest trailer without its own brakes your car may tow, capped at 750kg Australia-wide. Every caravan worth the name sits well above that, so this figure is about box trailers rather than vans.

Also called water damage.

Water finding its way into the walls, floor or roof, normally through a seam or around something screwed through the skin such as a window, a hatch or a light. Caught early it is a reseal, left alone it becomes structural.

A public vehicle scale you drive onto to have your car and van weighed as you actually pack them. It is the only way to know what your rig really weighs, and it usually costs less than a tank of fuel.

Also called WDH, load levelling hitch.

A hitch with spring bars that pushes some of the ball weight back onto the van's axles and forward onto the car's front axle, rather than letting it all press on the car's rear. It is usually talked about for longer, heavier vans. It changes how the weight is shared, it does not remove any weight from the car.