Oh The vehicle’s GVM, or Total volume of vehiclesis the amount of weight you can carry combined with the total mass of the vehicle (called the curb weight).
If your curb weight is 2500kg and the payload is 650kg, the total mass of the vehicle is 3150kg. This means you can add or carry 650kg of accessories or passengers before exceeding the GVM.
While 650kg seems reasonable, that can be quickly eaten up with barwork, winches, drawers and long-range fuel tanks, which is why GVM upgrades are so popular with four-wheel drivers, because you are legally allowed to carry more weight. GVM increased on factory offer.
What is a GVM upgrade?
A GVM upgrade involves the professional fitment of an aftermarket suspension kit designed, tested and approved in Australia to increase the factory GVM, allowing you to legally carry more weight.
Typically, this means minimally replacing the factory springs, shock absorbers and stock suspension components; Brake and tire upgrades may also be needed or even a full replacement axle upgrade.
This is different from simply fitting an aftermarket suspension kit, although most GVM upgrades will also increase the vehicle’s ride height from the factory, as well as provide a higher payload capacity figure. will
Why would you need a GVM upgrade?
If you’re moving payload data consistently or regularly close to the factory GVM, you’re an excellent candidate for a GVM upgrade. If you exceed the factory payload figures provided by your vehicle’s manufacturer, your 4WD is now considered to be in an off-road condition.
Police have been targeting overloaded 4WDs and trailers and especially in recent times, so there is a real risk of you getting caught. If your vehicle exceeds the factory GVM figure, it will also void your insurance in the event of an accident. It’s not worth the risk at all; You’ll either need to put your car on a serious diet, or spend the cash on a GVM upgrade.
Pre-Registration GVM Upgrades
If you’ve just signed on the dotted line for a new 4WD, there’s an option to upgrade the factory GVM before registering for the first time. Detailed and expensive testing is done by authorized suspension manufacturers during development, and upgrades are granted by the federal Department of Infrastructure and Transport after passing the relevant tests.
This means that the engineering leg work is basically done for you, and the new GVM kit will be supplied with the correct certification and compliance plates. Offering high GVM from day one, when fitted by an authorized agent. Sorry, DIYers, this isn’t a job you can handle on your own.
There are many benefits when choosing a pre-registration GVM upgrade, some of which we’ll touch on later in this article. Most important, however, is the cost, as it is an inexpensive exercise since an automotive engineer does not need to sign off on an individual installation. This certification was completed when the suspension kit was tested for compliance and met the minimum ADR safety requirements.
GVM upgrade after registration
This pre-registration is a bit more involved and expensive than a GVM upgrade, as laws vary from state to state. We spoke to Tough Dog’s Simon Vella about this, as he is an expert in the field of suspension development and GVM upgrades.
Simon tells us.
“Both Western Australia and the Northern Territory have a different process compared to other Australian states which is based on a type of approval system. This means that everything we do at Tough Dog Suspension, we have pre-approval. There is an upgrade approval agreement with any state and territory transport departments. Basically, those living in WA or NT don’t need to have a signatory to endorse a Tough Dog GVM upgrade. .
When asked about other Australian states, Simon said: “When it comes to the rest of the country, including Queensland, New South Wales, Victoria, Tasmania, South Australia and the ACT, the signatory for must be in place. Verify any post-registration GVM upgrades. You will need an authorized State Engineering signatory to perform the necessary upgrade inspection and supply certification.
“The signatory may require access to our test data and reports for which federal approval (pre-registration) has been granted, in order to verify certification.
“We have a list of engineers on the Tough Dog website who can assist with GVM upgrades after registration. As we are based in NSW, we use John from Consulmotive in Peakhurst NSW, and the process The cost is usually around $1000, but it will vary from vehicle to vehicle and job to job, but it gives you a ballpark figure.”
how much does it cost?
It’s going to come down to your own vehicle, and the components needed to do the job. For example, the parts needed to upgrade a VW Amarok to a maximum GVM of 3500kg using Bilstein shock absorbers and H&R coil springs will set you back $5899 from Advanced Installation Service in Emu Heights, NSW. This is a drive-in drive-out price that includes parts, labor and engineering certification post-registration.
If we look at the Ironman 4×4 GVM upgrade for the petite JB74 Suzuki Jimny, increasing the GVM from 1435kg to 1785kg, you’re looking at a minimum of $2571 pre-registration for parts alone, which works out to around $3000. Is. go After registration, the figure is said to be around $3700 to $4000 for the Jimny Drive-In-Drive-Out, according to posts on various Jimny pages and forums found online.
If we look at the higher end of the scale, upgrading the rear axle for greater axle load (and track width optimization) on a 79 series Land Cruiser, Brent of BAW Automotive in Queensland has provided us with these figures. are provided.
“Supply and install for a GVM upgrade starts at $17,000. That includes parts, labor and engineering,” says Brent. “Especially with GVMs, no brand is allowed to sell only parts. and all must be installed by commercial professionals. Engineering and labor must be part of the package and cannot be costed separately, as this gives the impression that you can only buy parts.
“In terms of cost at this stage, there’s not a lot of difference – however, if we’re talking about a pre-registration of a 70-series Land Cruiser, it allows you to go over 50mm in total in the suspension. At this height, it also allows 35-inch tires to be placed legally and to federally approved standards. With the GVM upgrade, this takes away from your break-to capability. Simply put – post-rego, you won’t be able to take as large objects as you’d like if you pre-set it. “
“The maximum gross vehicle mass upgrade you can get with a four-wheel setup is 4495kg, which makes it drivable under a standard vehicle licence. You can go up to a six-wheel setup. There are, but that’s a whole different kettle of fish and a whole different vehicle license.”
Tire and wheel load ratings
It’s worth noting that if you increase your vehicle’s GVM, you may also need to upgrade your tires and wheels, as the factory offering may not meet the new load rating requirement. For example, if the rear axle load limit is 3000kg, then each rear wheel would need to be rated at 1500kg or above to handle this load legally and safely.
Tires also have load ratings, with aftermarket light truck tires typically offering higher load ratings than passenger tires installed on most new vehicles. We won’t go into the details because it’s quite the rabbit hole, but tire and wheel upgrades are things to be aware of when upgrading your vehicle’s GVM and increasing tire size.
That’s why you need to talk to a knowledgeable and experienced suspension specialist before getting the job done, so you get the job done right the first time and don’t waste time and money.
What are the consequences of a GVM upgrade?
When we caught up with Simon Vella from Tough Dog Suspension at the Sydney 4X4 Show, he said the number one question he gets from punters at the show, especially those new to the 4×4 game, is whether they want a quick GVM up. Need a grade?
The other major comment was from people who had saved up to build their dream car, and had a GVM upgrade, but the car was now borderline dangerous to drive. This is because the spring rate used in the GVM upgrade kits is much higher than factory to handle the maximum load. Take that load out, and the car is now a lot more.
“The first thing people need to do when it comes to GVM upgrades is to qualify their vehicle to determine if they need a GVM upgrade,” Simon told us. Required.” “Load your vehicle, put it on a set of scales and weigh it, so you know exactly what the trip-ready vehicle weighs before you decide you need a GVM upgrade.” Go.”
In addition to the costs of the GVM upgrade, end users are reporting poor ride quality unless loaded, additional component costs, and the fact that you have to replace all the part numbers specified on the GVM upgrade kit. Should run.
So, if for example you want to run longer shock absorbers in an attempt to get more suspension travel, you can’t. You must use every item that comes with the GVM upgrade kit, signed off by an automotive engineer as part of the approval process.
Having seen the approval process in person, I can confirm that the engineer will inspect the vehicle, and take pictures of every part number of every part that has been upgraded, to see that they are GVM. The part numbers listed by the manufacturer of the upgrade kit are exactly the same. So, while a GVM upgrade is a useful addition for many four-wheel-drive tourers, it’s not for everyone.
A big shout out to the following people who helped provide information for this article. These companies specialize in 4WDs and suspension upgrades as well as GVM upgrades.
Simon from Tough Dog Suspension
Phone: (02) 9672 8899
Brent from BAW Automotive
Phone: 0417 783 415
Jeremy from Advanced Installation Services.
Phone: (02) 4739 9009