Is Your 4WD Overweight? How to Check Your GVM Legally in WA

Written By Rebekah Jackson

Is Your 4WD Overweight? How to Check Your GVM Legally in WA

Back from a summer trip up north?

Noticing the rear sagging a bit more than it used to.
Towing feels less stable.
Braking feels heavier.

We’ve had a steady run of locals from Busselton, Vasse and Dunsborough come in lately asking the same thing:

“Am I actually overweight?”

If you are touring, towing a caravan, or carrying tools every day around the South West, it is very easy to creep over your legal GVM without realising it.

Here is how to check properly and what it means for you.

What Is a GVM and Why It Matters in WA

GVM stands for Gross Vehicle Mass.

It is the maximum legal weight your vehicle is allowed to carry. That includes:

  • The vehicle itself

  • Fuel

  • Passengers

  • Camping gear or tools

  • Bullbar, winch, drawers, roof racks

  • Tow ball download from your caravan

If you are over that number in WA, you are technically non compliant.

That can mean fines, insurance issues, and more importantly, reduced braking and stability on regional roads.

Out here, that matters.

We drive long distances. We tow. We hit corrugations. We deal with heat and load. An overloaded 4WD does not handle that well.

Why We See So Many Overweight 4WDs in Busselton

Around Busselton and the South West, most 4WDs are doing more than one job.

Work during the week.
Caravan or boat on the weekend.
Trip up to Coral Bay or Karijini once a year.
Beach runs at Abbey or Siesta Park.

The problem is the weight builds up slowly.

You add:

  • Steel bullbar and winch

  • Dual battery system

  • Drawer setup

  • Fridge

  • Awning

  • Recovery gear

  • Tow ball weight

Individually they seem small. Together they push you over.

We regularly weigh vehicles that are 200 to 400kg heavier than the owner expected.

Am I Over My GVM If My 4WD Is Sagging?

Sagging is one of the biggest warning signs.

If the rear drops noticeably when loaded, that tells you:

  • The suspension is working hard

  • The weight is significant

  • You may be close to or over your limit

Sag alone does not confirm you are illegal. But it is a good reason to check.

Especially if towing feels unstable on the Busselton Bypass or regional highways.

How to Check Your GVM Legally in WA

This is the straightforward way to do it.

1. Check Your Compliance Plate

Open the driver’s door. Look at the plate.

You will see:

  • GVM

  • Front axle limit

  • Rear axle limit

That is your legal maximum.

2. Load It Exactly As You Travel

Full of fuel.
Passengers in.
All gear packed.
Caravan attached if you tow.

Do not guess. Load it properly.

3. Use a Public Weighbridge

There are weighbridges around the South West.

Get:

  • Total vehicle weight

  • Front axle weight

  • Rear axle weight

Compare those numbers to your compliance plate.

If you are over, even slightly, you are technically over GVM.

The Tow Ball Weight Trap

This catches people out all the time.

Tow ball download counts toward your GVM.

You can be under your towing capacity but still over your GVM.

Two different numbers. Two different limits.

We see this a lot with caravan setups around Busselton and Dunsborough. Everything feels fine until it is actually weighed.

What Happens If You Keep Driving Overweight

Beyond fines, here is what really matters.

An overloaded 4WD:

  • Takes longer to stop

  • Handles poorly in emergency situations

  • Puts extra stress on brakes and tyres

  • Wears suspension components faster

  • Increases the chance of failure on corrugations

For tradies and fleet vehicles, it also becomes a compliance and liability issue.

If you are running work utes around the South West loaded every day, it is worth knowing your numbers.

When a GVM Upgrade Makes Sense

If you regularly:

  • Tow a caravan

  • Carry tools daily

  • Tour long distance in WA

  • Have added multiple heavy accessories

Then a certified Dobinsons GVM upgrade may be the right solution.

A proper GVM upgrade:

  • Increases your legal load capacity

  • Upgrades suspension to handle that weight safely

  • Keeps you compliant in WA

  • Improves stability under load

  • Reduces sag and bottoming out

It is not about lifting your vehicle for looks.

It is about keeping your setup safe, legal and stable on South West roads and long WA trips.

For Local 4WD Tourers

If you are planning another run north next season, or towing regularly out of Busselton, it is worth checking before the next trip.

Corrugations and long highway runs expose weak suspension and overloaded setups quickly.

A simple load assessment now can save a lot of trouble later.

For Local Tradies and Fleet Vehicles

If your ute is loaded with tools every day in Busselton, Vasse or Yalyalup, small overloads add up over time.

Knowing your actual weights protects:

  • Your drivers

  • Your business

  • Your vehicles

  • Your insurance

We work with plenty of local businesses doing exactly this.

Not Sure Where You Sit?

If your 4WD feels different after summer, bring it in.

We can:

  • Inspect your suspension

  • Assess your load setup

  • Talk through your actual weights

  • Advise whether a GVM upgrade is needed

No pressure. Just clear advice based on how you actually use your vehicle around the South West.

Safe. Compliant. Ready for the next trip.

More info - read more here.

To get a quote - fill out our form.

Rebekah Jackson
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