Will Airbags Bend or Crack Your 4WD Chassis?

Aug 26, 2026

If you've been looking at airbag suspension for your vehicle, you've probably heard this one before:

"Don't put airbags on it — they'll bend or crack your chassis."

It's one of the most common myths we hear about 4WD airbags and airbag suspension.

We've been selling suspension, airbags and 4WD suspension kits since 1974, and like a lot of things you hear on Facebook and internet forums, there's a bit more to the story.

The simple answer is:

A correctly selected and correctly installed airbag suspension kit isn't going to bend or crack your chassis simply because you've fitted airbags.

But there are some important things you need to understand.

Airbags aren't a magic fix for an overloaded 4WD, and they're certainly not a way of increasing your GVM.

Let's have a look at the facts.

4WD Suspension Experience Since 1974

We have been selling airbags since 1974, when our founder, Ed Mulligan, started Opposite Lock 4WD Accessories. Since then, we have sold hundreds of thousands of airbag kits and, in all that time, we have only had two customers experience a bent or cracked chassis — and in both cases, it came down to human error, not the airbag system itself.

That's a pretty good track record.

Hundreds of thousands of kits sold, with virtually every one doing exactly what it was designed to do.

If you use common sense, don't overload your vehicle, fit the correct kit and drive to the conditions, there's no reason to be scared of airbags.

At 4WD World, we believe in doing it once and doing it properly:

The right product, for the right vehicle, doing the right job.

And when it comes to airbags, that's what matters.

First Up — Airbags Don't Increase Your GVM

This is probably the most important thing to understand when you're looking at airbags for towing or load carrying.

Putting airbags on your vehicle does not increase the vehicle's GVM.

If your 4WD has a GVM of 3,500kg, fitting a set of load assist airbags doesn't suddenly make it a 4,000kg vehicle.

The same applies to your axle ratings and the manufacturer's limits.

Airbags support the suspension — they don't increase the legal carrying capacity of the vehicle.

This is something we're pretty strong on at 4WD World.

If you're carrying a heavy canopy, tools, camping gear or towing a caravan, we want to know what the actual load is before recommending a 4WD airbag suspension kit.

So Where Does the Chassis Cracking Story Come From?

A lot of the concern comes from looking at a leaf-sprung ute and thinking:

"The airbag is sitting between the axle and chassis, so all that air pressure must be pushing into the chassis."

Well, yes — the suspension has to transfer the vehicle's load between the axle and chassis.

But that's already happening.

Your leaf springs are already transferring the load through the suspension and into the chassis.

An airbag is there to assist the existing suspension and provide additional support when the vehicle is loaded.

Airbags for Leaf-Sprung 4WDs and Utes

Most of the utes we deal with — Toyota Hilux & LandCruiser, Ford Ranger, Isuzu D-MAX, Mazda BT-50, Mitsubishi Triton, Holden Colorado, Nissan Navara, LDV T60, SsangYong Musso and plenty of others — use leaf springs in the rear.

They're also some of the most popular vehicles for airbag suspension kits.

Why?

Because the load these vehicles carry can change dramatically.

You might drive your ute empty during the week, then add a canopy, tools, fridge, drawers, camping gear and other equipment. On the weekend, you might hook up a caravan.

That's a very different load from driving around empty.

One option is to fit very heavy constant-load leaf springs. The downside is that the suspension can become quite harsh when the vehicle isn't carrying the load those springs were designed for.

This is where load assist airbags can make a lot of sense.

You keep your existing suspension and use the airbags to provide additional support when you need it.

Thor Airbags for the Toyota Hilux

A good example is the Toyota Hilux.

For the 2025 Hilux, we supply the Thor Airbag Suspension Kit, designed for the N80/N90 Hilux application.

This type of airbag suspension for Hilux is designed to provide additional support when the vehicle is carrying a heavy load or towing.

You don't need to run the airbags at maximum pressure all the time. The idea is to adjust the air pressure to suit the load.

Looking for Hilux airbags?

Shop Thor Airbag Suspension for Toyota Hilux

If you're searching for Toyota Hilux airbags, Hilux airbag suspension or Hilux load assist airbags, this is the type of application we're talking about.

What About Airbags on a Chevrolet Silverado 2500HD?

This is another area where we get a lot of questions.

The Chevrolet Silverado 2500HD is a very capable towing vehicle and is commonly used for large caravans, horse floats, trailers and other heavy towing applications.

For the Silverado 2500HD, we supply the Polyair Bellows Ultimate airbag suspension kit.

The system is designed specifically for the Silverado application and allows the air pressure to be adjusted depending on the load.

Polyair Ultimate airbags for Silverado 2500HD

Chevrolet Silverado 2500HD towing a caravan with Polyair airbag suspension

Shop Polyair Bellows Ultimate – Chevrolet Silverado 2500HD

This is a good example of why airbag suspension for towing can be useful. You may have a very different rear axle load when you're towing a caravan compared with when you're driving the truck empty.

Being able to adjust the airbag pressure gives you another way of setting up the suspension for the job you're doing.

But again, the airbags don't increase the Silverado's GVM or towing capacity.

What About the Ford Ranger Raptor?

The Ford Ranger Raptor is a completely different vehicle again.

It's designed with more suspension travel and off-road capability than a standard Ranger. Its Fox suspension provides a softer ride and isn't primarily set up for load carrying or towing.

That means you need to be careful when choosing Ranger Raptor airbags.

You can't just fit any generic airbag kit and assume it's going to work properly with the vehicle's suspension.

For the Ranger Raptor, we supply the BOSS Airbag Suspension Kit, designed specifically for the Raptor application.

BOSS airbags for Ford Ranger Raptor

Shop BOSS Airbag Suspension for Ford Ranger Raptor

If you're searching for Ford Ranger Raptor airbag suspension, Ranger Raptor airbags or Raptor load assist airbags, make sure you're looking at a kit designed for the vehicle.

The correct brackets, mounting system and suspension travel all matter.

Airbags for Coil-Sprung 4WDs

Not all 4WD airbags go between the axle and chassis.

On coil-sprung vehicles, you can also use in-coil airbags.

A good example is the Toyota LandCruiser 300 Series.

The Polyair Ultimate in-coil system fits inside the existing coil spring and provides additional support when the vehicle is carrying a load or towing.

Polyair Ultimate in-coil airbags for LandCruiser 300 Series

Toyota LandCruiser 300 towing a caravan off-road with Polyair Ultimate suspension support.

Shop Polyair Ultimate In-Coil Airbags – LandCruiser 300 Series

This is a very popular type of airbag suspension for 300 Series LandCruiser owners who are touring, carrying extra weight or towing.

Again, the idea isn't to make the vehicle carry more weight than it is legally rated to carry.

It's about helping the existing suspension deal with the load more effectively.

Can Airbags Actually Damage a Chassis?

Let's be honest about this.

Any suspension system can cause problems if the wrong components are used, the installation is wrong or the vehicle is being overloaded or used outside its intended application.

But here's the thing — if you don't overload your vehicle, you drive to suit the road conditions and you use a bit of common sense, you shouldn't have a problem.

Your 4WD isn't indestructible just because you've fitted airbags. You still need to drive it sensibly.

If you're overloaded, driving through holes and corrugations at excessive speed, landing heavily after jumps or treating the local tracks like you're competing in the Finke Desert Race, you're putting enormous forces through the entire vehicle.

That's not an airbag problem. That's a driver and load problem.

A chassis can be damaged by overloading, excessive impact, accidents, poor modifications or simply driving a vehicle harder than it was designed to be driven.

And in our experience, when you see a bent or cracked chassis, you need to look at what the vehicle has been carrying and how it has been driven before automatically blaming the airbag kit.

Use the right product, don't overload the vehicle, install it correctly and drive to the conditions. Use a bit of common sense and you shouldn't have an issue.

Airbags are there to assist the suspension, help level the vehicle and support it in handling the load it was designed to carry.

So when someone says, "Airbags crack chassis," we'd say that's a pretty big generalisation.

The product itself isn't the problem when it has been correctly selected and correctly installed.

More Air Doesn't Mean More Carrying Capacity

This is another big one.

If your airbag system is rated to operate up to a certain pressure, that doesn't mean you should simply pump it to maximum pressure every time you load the vehicle.

The pressure should be adjusted to suit the load and the vehicle.

The whole point of adjustable airbag suspension is that you can adjust it.

Empty ute?
Less air pressure — we recommend a minimum of 5 PSI, as the airbags then also act as a bump stop which is removed when fitting airbags.

Loaded ute?
More air pressure.

Towing the caravan?
Adjust it to suit the load.

That's one of the biggest advantages of airbag suspension for towing — you get an air-adjustable ride that can be adjusted to suit the load.

The Biggest Mistake? Buying the Wrong Airbag Kit

This is where we think you need to be careful.

There are plenty of airbag suspension kits for sale online, but that doesn't mean every kit is right for every vehicle.

That's why we ask questions.

What do you drive?
What year is it?
Is it standard height or lifted?
What are you carrying?
Are you towing?
How heavy is the caravan?
What is the tow ball weight?
Do you go off-road?
Is the load constant or only occasional?

We want to know what you're actually doing with the vehicle.

Because the best airbag suspension setup isn't necessarily the most expensive one.

It's the one that's right for your vehicle and what you use it for.

So, Will Airbags Bend or Crack Your Chassis?

Here's our answer:

Not simply because you've fitted airbags.

A correctly selected and correctly installed airbag suspension kit is designed to work with the vehicle's existing suspension and provide additional support when the vehicle is loaded.

If you don't overload your vehicle, stay within the vehicle's GVM and axle ratings, maintain the suspension correctly and drive to suit the road conditions, there is no reason to be scared of fitting airbags.

Common sense goes a long way.

Airbags don't increase your GVM.

Used correctly, airbags are a great way to improve load carrying and towing ability of your vehicle.

They can help with:

Rear-end sag
Improved tyre wear
Improving suspension longevity
Headlight aim
Giving a more comfortable air-adjustable ride
Body roll
Sway
Ride height
Maintaining better vehicle safety when loaded

And that's really what they're there for.

Supporting the vehicle when it needs more support.

Airbag Suspension FAQs

Can airbags crack a 4WD chassis?

Not simply because you've fitted airbags. A correctly selected and correctly installed airbag suspension kit is designed to work with the vehicle's existing suspension and provide additional support when the vehicle is loaded.

Do airbags increase my vehicle's GVM?

No. Airbags support the suspension — they don't increase the legal carrying capacity of the vehicle. The vehicle's GVM, axle ratings and manufacturer's limits still apply.

Are airbags useful when towing a caravan?

Airbag suspension is an excellent choice when towing infrequently. Airbags provide additional support when towing and allow the air pressure to be adjusted to suit the load.

Should I run my airbags at maximum pressure?

No. The pressure should be adjusted to suit the load and the vehicle. The whole point of adjustable airbag suspension is being able to adjust it for different loads.

How do I choose the right airbag kit for my 4WD?

The right setup depends on your vehicle, year, suspension height, what you're carrying, whether you're towing, tow ball weight, off-road use and whether the load is constant or occasional. The best setup is the one that's right for your vehicle and how you use it.