GVM Upgrade FAQs: Everything You Need to Know About GVM Upgrades

Posted In: Suspension

When it comes to vehicle modifications, Gross Vehicle Mass (GVM) upgrades are among the most discussed topics, especially for tradies using their vehicles to carry equipment for jobs, or travellers who carry adventure gear for a weekend getaway.

The demand on your vehicle can quickly exceed its designed GVM when you stack it full of equipment, toys and accessories. Understanding GVM upgrades is essential for safety, legality, and performance.

We’ve put together the answers to some of the questions we hear most.

  1. What is GVM?
  2. What is a GVM upgrade?
  3. Why consider a GVM upgrade?
  4. Is a GVM upgrade legal?
  5. How is a GVM upgrade done?
  6. Can I upgrade any vehicles GVM?
  7. Will a GVM upgrade affect my vehicle’s warranty?
  8. How much does a GVM upgrade cost?
  9. Choosing a provider to upgrade your GVM

1. What is GVM?

Vehicle manufacturers set Gross Vehicle Mass (GVM) limits for each vehicle model, this determines the maximum loaded weight of a vehicle while driving on the road.

When determining the GVM, manufacturers take into account:

  • Strength of vehicle’s frame
  • Capacity of the suspension and brakes
  • Maximum weight the tyres can support

It’s important to note that GVM is different from Gross Combination Weight (GCW), which is the total weight of a vehicle and its trailer(s) when loaded.

2. What is a GVM upgrade?

A GVM upgrade involves replacing your original vehicle suspension with aftermarket suspension including heavy springs and shock absorbers which are more capable and designed to carry greater weight, without sacrificing handling, functionality, and safety. This allows you to legally carry a higher allowable weight, including the vehicle itself, accessories, passengers, fuel, and cargo.

All Gross Vehicle Mass (GVM) upgrades undergo thorough testing and approval by the Department of Infrastructure, Transport. Additionally, part of the GVM enhancement process involves assessing and confirming axle load limits to allow for increased allowable weight on each axle.

This upgrade is crucial for vehicles that are used to carry heavy loads or are loaded up with accessories, ensuring the vehicle remains within legal weight limits.

3. Why consider a GVM upgrade?

GVM upgrades allow you to carry bigger loads without compromising performance or handling. There are 5 key reasons you would consider a GVM upgrade:

Heavy Loading

Regularly carrying tools, equipment, or cargo that brings the vehicle close to or over its original GVM. This is common in trade professions where carrying heavy tools and supplies is a daily necessity.

Adding Accessories

Installing additional equipment like bull bars, winches, toolboxes, or canopy setups can significantly increase the weight of your vehicle.

Perfect for off-road enthusiasts who equip their vehicles with various modifications for better functionality and protection.


Overloaded vehicles can suffer from poor handling and increased stopping distances.


Operating a vehicle over its GVM can result in fines and affect insurance and warranty claims.


Upgrades can improve the overall driving experience, making vehicles more stable and capable under load.

4. Is a GVM Upgrade Legal?

Yes, GVM upgrades are legal, provided they are performed by a qualified technician and certified according to the national standards. After the upgrade, your vehicle will be inspected, and you will receive a modification plate to be affixed next to the manufacturer’s plate, indicating the new GVM.

5. How is a GVM Upgrade Done?

The process typically involves replacing or upgrading components of the vehicle’s suspension system, such as springs and shock absorbers, to support additional weight.

Some upgrades may also include modifications to the brakes, wheels, and tyres to ensure overall vehicle safety and performance.


The first step is to determine if your vehicle is a candidate for a GVM upgrade. This usually involves weighing your vehicle in its typical operating condition.

Upgrade Kit Installation

If an upgrade is deemed necessary, a certified service center can install a GVM upgrade kit. These kits often include new springs, shock absorbers, and sometimes additional modifications to brakes or axles.


After the upgrade, the vehicle must be inspected by a certified engineer who will issue compliance documentation necessary for updating your vehicle’s registration details.

6. Can I Upgrade Any Vehicle’s GVM?

Not all vehicles are eligible for GVM upgrades. The availability of an upgrade kit and the possibility of upgrading depend on the vehicle make, model, and year. It’s best to consult with DAPCO Bunbury to determine if your vehicle is eligible.

Some of the most popular vehicles we have kits for are:

Toyota Landcruiser 78/79 Series GVM Upgrades
Toyota Landcruiser 100 & 105 Series GVM Upgrades
Toyota Landcruiser 200 Series GVM Upgrades
Toyota Landcruiser 300 Series GVM Upgrades
Ford Ranger PX, PXII, PXIII GVM Upgrades
Nissan Patrol GU & Y61 GVM Upgrades
Isuzu M-UX GVM Upgrades
Mazda BT-50 GVM Upgrades

7. Will a GVM Upgrade Affect My Vehicle’s Warranty?

This depends on your vehicle’s manufacturer and the specifics of the upgrade. Some manufacturers may void the warranty if modifications are made, while others may not. It’s crucial to consult with your manufacturer and the upgrade provider to understand the potential implications.

8. How Much Does a GVM Upgrade Cost?

The cost of a GVM upgrade can vary significantly based on the vehicle model, the components required for the upgrade, and the labour involved. Generally, prices can range from a few thousand dollars to over ten thousand dollars for more comprehensive modifications.

9. Choosing a Provider for GVM Upgrades

Selecting the right provider for a GVM upgrade is critical. Look for certified and experienced technicians who specialise in vehicle modifications. Ensure they use high-quality components and offer a warranty for their work.

Workshops like DAPCO Bunbury are licensed as a 2nd stage manufacturer, meaning we can legally increase the weight carrying capacity of suitable vehicles. Find out more about our GVM upgrades here.

GVM upgrades are a significant modification for vehicle owners who need to safely and legally increase their load-carrying capacity. Understanding the process, benefits, and legalities ensures that you make informed decisions about enhancing your vehicle’s performance and compliance. Always consult with professional providers to ensure your vehicle is up to the task, legally compliant, and safe on the road.