Every second phone call to the shed starts the same way. "Mate, is the van right on the back of the ute or not?" Usually the bloke asking has already hooked up, already filled both water tanks, and is standing in the driveway wondering if he's about to get pulled over at the next weighbridge on the way to Noosa. Tony's answer is always the same. Pull the compliance plates off both the tow vehicle and the van, then run the numbers before you turn a wheel, not after you're doing 100 on the Bruce Highway with a wobble showing up in the mirrors.
We've been towing vans, box trailers and tandem car trailers out of our place west of Brisbane for a long time now, and the one thing that never changes is how often people guess instead of check. GVM, GCM, ball weight, tow ball download, these aren't suggestions from a brochure, they're hard limits set by the manufacturer, and going over them is exactly how an insurer finds a reason to say no after something goes wrong on the range coming down from Toowoomba.
Here's the routine we actually use, and it takes about fifteen minutes with a cup of tea in hand.
First, find the tare weight of the van and the payload capacity, then walk around and honestly total up everything that's loaded in it, water, gas bottles, the generator, camp chairs, the esky, clothes, the lot. People are shocking at underestimating this. A full water tank alone can be eighty to ninety kilograms, and two of them plus a hot water system tank adds up fast. Tony's rule from thirty years of towing is to weigh loaded, not guess loaded, at a public weighbridge if you can find one on your route, because water and stubbies feel light until you've got three tanks of it sloshing around behind you.
Second, work out your tow ball weight, which should usually sit somewhere around ten percent of the total van weight, give or take what the manufacturer specifies. Too light and the van will sway behind you on any decent crosswind coming across the Lockyer Valley. Too heavy and you're overloading the rear axle of the tow vehicle, which changes your steering and your braking without you feeling it happen gradually, it just goes wrong all at once, usually when a truck overtakes you.
Third, and this is the one blokes skip most often, check your GCM (gross combination mass): not just the GVM of the ute on its own. You can be perfectly legal on the tow vehicle's own weight and still be over GCM once the van's added, because GCM is the combined limit for vehicle plus trailer plus everything in both. A lot of dual cab utes get modified with bull bars, canopies, drawer systems and long-range tanks before they ever tow anything, and every one of those additions eats into what's left for the van. We've seen utes that were 200 kilograms into their GCM limit before the trailer was even hooked up, purely from accessories.
This is where we stopped doing it on the back of an envelope and started using the towing weights calculator at https://freeonlinetools.au/tools/towing-weights-calculator.php. You punch in your tow vehicle's kerb weight, GVM and GCM straight off the compliance plate, then add the van's tare and its loaded weight, and it spits back whether you're within GVM, GCM and ball weight limits, plus how much headroom you've actually got left for extra payload like tools, camp gear or the dog. It's the same maths Tony used to do with a notepad and a calculator from the servo, just faster and harder to stuff up.
The other tool that's saved us a few arguments in the driveway is the trailer load planner at https://freeonlinetools.au/tools/trailer-load-planner.php. This one's more about where the weight sits inside the van or trailer rather than just the total. Loading heavy items like the generator or a full tool box too far back drags weight off the tow ball and encourages sway, while loading everything up front can overload the ball and the front axle of the tow vehicle. The planner helps you think through front-to-back distribution before you start Tetris-ing gear into the boot at eleven at night, which is when most bad packing decisions get made.
A few extra things we've learned the hard way over the years, mostly from Tony's earlier trips before any of this was checked properly. Tyre pressures on both the tow vehicle and the van need adjusting for the extra load, not left at the unladen setting, check the door jamb sticker and the van manufacturer's loaded pressure recommendation. Electric brakes on the van need a gain setting that matches the load, and it's worth testing the brake controller on a quiet street before you're relying on it going down the range with a laden van behind you. And mirrors: proper towing mirrors, not the standard ones: are non-negotiable once the van's wider than the ute, especially merging on the Ipswich Motorway in peak traffic.
None of this is about being precious or over the top with red tape. It's about not finding out you were over GCM the hard way, whether that's a fine at a weighbridge on the Cunningham Highway or, worse, a fishtailing van at highway speed with the family in the back seat. Fifteen minutes with the compliance plates and a calculator before you leave the driveway beats a slow drive home wondering if the trailer's about to do something stupid.
We run this check before every single trip now, van holiday or work trailer, and it's become as automatic as checking the oil. Takes less time than packing the esky, and it's the difference between towing with confidence and towing with your fingers crossed.
We've been towing vans, box trailers and tandem car trailers out of our place west of Brisbane for a long time now, and the one thing that never changes is how often people guess instead of check. GVM, GCM, ball weight, tow ball download, these aren't suggestions from a brochure, they're hard limits set by the manufacturer, and going over them is exactly how an insurer finds a reason to say no after something goes wrong on the range coming down from Toowoomba.
Here's the routine we actually use, and it takes about fifteen minutes with a cup of tea in hand.
First, find the tare weight of the van and the payload capacity, then walk around and honestly total up everything that's loaded in it, water, gas bottles, the generator, camp chairs, the esky, clothes, the lot. People are shocking at underestimating this. A full water tank alone can be eighty to ninety kilograms, and two of them plus a hot water system tank adds up fast. Tony's rule from thirty years of towing is to weigh loaded, not guess loaded, at a public weighbridge if you can find one on your route, because water and stubbies feel light until you've got three tanks of it sloshing around behind you.
Second, work out your tow ball weight, which should usually sit somewhere around ten percent of the total van weight, give or take what the manufacturer specifies. Too light and the van will sway behind you on any decent crosswind coming across the Lockyer Valley. Too heavy and you're overloading the rear axle of the tow vehicle, which changes your steering and your braking without you feeling it happen gradually, it just goes wrong all at once, usually when a truck overtakes you.
Third, and this is the one blokes skip most often, check your GCM (gross combination mass): not just the GVM of the ute on its own. You can be perfectly legal on the tow vehicle's own weight and still be over GCM once the van's added, because GCM is the combined limit for vehicle plus trailer plus everything in both. A lot of dual cab utes get modified with bull bars, canopies, drawer systems and long-range tanks before they ever tow anything, and every one of those additions eats into what's left for the van. We've seen utes that were 200 kilograms into their GCM limit before the trailer was even hooked up, purely from accessories.
This is where we stopped doing it on the back of an envelope and started using the towing weights calculator at https://freeonlinetools.au/tools/towing-weights-calculator.php. You punch in your tow vehicle's kerb weight, GVM and GCM straight off the compliance plate, then add the van's tare and its loaded weight, and it spits back whether you're within GVM, GCM and ball weight limits, plus how much headroom you've actually got left for extra payload like tools, camp gear or the dog. It's the same maths Tony used to do with a notepad and a calculator from the servo, just faster and harder to stuff up.
The other tool that's saved us a few arguments in the driveway is the trailer load planner at https://freeonlinetools.au/tools/trailer-load-planner.php. This one's more about where the weight sits inside the van or trailer rather than just the total. Loading heavy items like the generator or a full tool box too far back drags weight off the tow ball and encourages sway, while loading everything up front can overload the ball and the front axle of the tow vehicle. The planner helps you think through front-to-back distribution before you start Tetris-ing gear into the boot at eleven at night, which is when most bad packing decisions get made.
A few extra things we've learned the hard way over the years, mostly from Tony's earlier trips before any of this was checked properly. Tyre pressures on both the tow vehicle and the van need adjusting for the extra load, not left at the unladen setting, check the door jamb sticker and the van manufacturer's loaded pressure recommendation. Electric brakes on the van need a gain setting that matches the load, and it's worth testing the brake controller on a quiet street before you're relying on it going down the range with a laden van behind you. And mirrors: proper towing mirrors, not the standard ones: are non-negotiable once the van's wider than the ute, especially merging on the Ipswich Motorway in peak traffic.
None of this is about being precious or over the top with red tape. It's about not finding out you were over GCM the hard way, whether that's a fine at a weighbridge on the Cunningham Highway or, worse, a fishtailing van at highway speed with the family in the back seat. Fifteen minutes with the compliance plates and a calculator before you leave the driveway beats a slow drive home wondering if the trailer's about to do something stupid.
We run this check before every single trip now, van holiday or work trailer, and it's become as automatic as checking the oil. Takes less time than packing the esky, and it's the difference between towing with confidence and towing with your fingers crossed.
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