When you need a HiAce GVM upgrade and when you just carry less

Your HiAce is finished and you’re wondering whether it’s still legal to drive. A camper fit-out adds 400 to 700kg, according to Commercial Motor Group, which is most of the van’s payload. A HiAce GVM upgrade fixes that, but plenty of builds don’t need one.

How much does a HiAce camper conversion weigh?

A finished conversion typically adds 400 to 700kg to the van, and Commercial Motor Group puts the factory payload at somewhere near 1,000 to 1,200kg, varying with the model and the build year. It also tells owners to read the number off their own compliance plate instead of trusting a generic figure, and that’s the first thing to do.

Payload is the gap between what your van weighs empty and its gross vehicle mass, the maximum it’s legally allowed to weigh fully loaded. Both figures come from the compliance plate fitted to your van. Everything you added after it left the factory comes out of that gap, and so does every person and every bag in it.

Component weights published by Commercial Motor Group give you a rough tally before you get near a weighbridge.

Build item	Typical added weight
Bed frame and mattress	50-120kg
Drawer or storage system	40-90kg
Water tank, full	40-100kg
Kitchen unit	30-80kg
Dual battery system	30-60kg
Fridge	20-40kg

Water is the one people forget. Fill the tank and you’re hauling close to a kilogram for every litre in it, which Commercial Motor Group costs at 40 to 100kg on a typical build. The table above covers only the fit-out. Food, water containers, tools, bedding, bikes, a jerry can of fuel and two adults all sit on top of it.

Do I need a GVM upgrade, or can I just carry less?

You need a GVM upgrade only if the loaded van goes over its plated mass with the build, the water, the gear and everyone aboard, and a lot of HiAce campers scrape under if the owner is disciplined about packing. Weigh it loaded before you spend anything.

Total mass isn’t the only limit you can break. Each axle carries its own rating, and Commercial Motor Group suggests splitting the loaded weight so the front carries about 50 to 60 per cent and the rear takes the remaining 40 to 50 per cent. Get that balance wrong and you can bust an axle limit while the total still reads under GVM. A heavy drawer bank and a loaded bike rack both push weight backwards.

Before you commit to an engineering job, here is weight you can shed without touching the build, using the litre-for-kilogram water figure from Commercial Motor Group.

• Travel with the tank part filled and top up at taps, because every litre you carry is another kilogram.
• Leave the second battery out of the build if you spend most nights on powered sites.
• Carry one set of tools and spares rather than a full workshop.
• Move the heaviest items forward of the rear axle instead of into the tailgate drawers.
• Run the van over a public weighbridge fully loaded before a long trip rather than guessing.

Carrying less is best for a build that already comes in under the plate with room to spare, and for owners who travel light and alone. A GVM upgrade is best for owners who want a full water tank, two passengers, bikes and a tow ball load at the same time, permanently, without doing arithmetic at every trip.

What does a HiAce GVM upgrade involve and what does it cost?

A GVM upgrade is an engineering job that legally raises the loaded mass your van is rated to carry. Lovells breaks it into two halves: suspension hardware, meaning heavy-duty coil or leaf springs and matched shock absorbers, and the certification paperwork that lifts the approved rating. New springs on their own are not an upgrade. The paperwork is the part that makes it legal.

For a sense of scale, Bus 4×4 Group rates its secondary stage manufactured HiAce Commuter at a GVM of 4,300kg, which it says buys an extra 590kg on top of what the van left the factory rated to carry, with reworked front suspension and heavier rear suspension in the package, per its 2025 specification. That 590kg is roughly the weight of an entire mid-spec camper fit-out.

Timing changes the process. Lovells draws a firm line between an upgrade fitted before the van is first registered and one done to a van already on the road. The second route runs through your state or territory scheme, needs the work certified there, and ends with the registration record being amended. If your HiAce is already registered and already built, that is the path you’re on.

There’s no headline price, and anyone quoting one without seeing the van is guessing. Lovells publishes no fixed figure. What you pay turns on which van you own, which kit goes under it, who fits it, which certification route you take, and whether the work happens before registration or after. Get the hardware and the certification quoted as separate lines so you can see what you’re actually paying for.

One more warning worth taking seriously: Lovells says certification granted in one Australian state or territory will not necessarily be accepted across the border. If you register in one state and tour in others, ask about that before you book the job.

What happens if I’m caught over weight?

An overloaded van gets measured against its plated GVM, and the consequence scales with how far over the mark you are. Enforcement grades overloading rather than treating every kilogram the same.

The clearest published example of that grading sits with the National Heavy Vehicle Regulator, which sorts mass breaches under the Heavy Vehicle National Law into three bands. A substantial breach starts at whichever is greater, 105 per cent of the permitted maximum rounded up to the nearest tenth of a tonne, or half a tonne over. At 120 per cent, again rounded up the same way, it becomes severe. Anything under the substantial line is graded minor. That law governs heavy vehicles rather than every camper van, so read it as a guide to how seriously overloading is treated, not as the penalty schedule for your HiAce.

For a light van, the penalty and the roadworthy consequence are set by your state or territory, and they differ, so check with your own registration authority before assuming a small overload is a small problem. What is consistent everywhere is the paperwork question. If your van sits above its factory GVM, an inspector will want to see why that’s permitted.

Keep the file. Lovells tells owners to hang on to the invoices, the kit specification, the engineering or modification certificate, the plate details and the amended registration record. That folder is what backs you up when you register the van, when you sell it, when you claim on it and when someone pulls you over.

So the order of work is simple. Weigh the finished van loaded the way you actually travel, compare it to your own compliance plate, and check the axle split as well as the total. If you’re under on both, pack smarter and drive on. If you’re over, price a certified upgrade through your state’s scheme and keep every piece of paper it generates.