Do airbags increase towing capacity?

No. Airbags level the truck and improve how it handles ball weight, but legal towing capacity is set by GVM, GCM, axle limits and towbar rating — none of which suspension changes.

Airbags or heavier springs for towing a caravan?

Airbags for weekend towing, because you keep the factory ride when unhitched. Heavier springs suit trucks carrying permanent weight like a tray, canopy or slide-on camper.

Why does my truck feel unstable at highway speed with the van on?

Most often worn or under-damped shocks, sometimes combined with poor weight distribution. Adding stiffer springs usually makes it worse, not better.

Do I need an alignment after suspension work?

Yes. Any change in ride height alters camber, caster and toe. We align every truck after suspension work — skipping it is how owners end up replacing tyres early.

Best Suspension for Towing | RAM, Silverado & F-Series Australia

What problem are you actually trying to fix?

Suspension upgrades go wrong when owners buy a product instead of solving a symptom. A truck that sags 80 mm at the ball, a truck that porpoises at 100 km/h behind a van, and a truck that crashes over corrugations empty all need different answers. Start with the symptom.

Symptom	Usual cause	What usually fixes it
Rear sags when hitched	Ball weight exceeding spring rate	Airbag assist
Porpoising / floating at highway speed	Worn or under-damped shocks	Quality shock upgrade
Headlights pointing skyward	Rear sag changing attitude	Airbags plus correct load distribution
Constant load, always sitting low	Springs at end of life	Upgraded / heavy-duty springs
Harsh unladen ride after 'upgrade'	Springs too stiff for the truck's real use	Airbags instead of heavier springs
Sway under trucks passing	Weight distribution and damping combined	Setup review, not one part

Airbags: the right answer for most caravan owners

Airbag assist kits sit inside or alongside the rear springs and let you add support only when the van is hooked up. Unhitched, you drop the pressure and keep the factory ride. That flexibility is why airbags suit the typical Sunshine Coast owner who tows on weekends and drives an empty truck the rest of the week.

Levels the truck with ball weight applied, restoring headlight aim and steering feel
Adjustable — no permanent ride penalty when the truck is empty
Can be run with a compressor and in-cab control, or a simple manual valve setup
Does not increase GVM, GCM or legal towing capacity
Needs correct fitment and clearance checks; a rubbed airline is the most common DIY failure we repair

Upgraded springs: for trucks that carry weight all the time

If your truck has a tray, a canopy, tools, or a slide-on that lives on it permanently, heavier springs make sense — they hold the correct ride height all the time without you thinking about it. The trade-off is a firmer ride when the truck is empty, which is exactly why we don't recommend them for weekend-only towing.

Shocks: the most under-rated upgrade

Springs hold the weight; shocks control what the weight does next. Nearly every complaint about a towing truck feeling unstable at highway speed traces back to damping, not spring rate. Quality twin-tube or monotube shocks matched to the truck and its load transform how a heavy combination behaves on the Bruce Highway, and they do it without touching ride height or compliance.

Is a lift or upgraded suspension legal in Queensland?

Queensland allows modest suspension changes without certification, with limits on total lift including tyres. Beyond that you need engineering approval. Airbag assist kits fitted correctly generally sit within the rules because they don't change the vehicle's rated capacities. We'll tell you clearly where your build sits before we fit anything.

Suspension work never changes your legal towing capacity. GVM, GCM, tow ball down weight and towbar rating are what determine what you can legally tow — suspension only changes how well the truck handles what it's already allowed to carry.

A sensible upgrade order

1Weigh the combination and confirm ball weight and axle loads are within limits
2Fix worn components first — shocks, bushes, tyres — before adding anything
3Add airbag assist if the truck sags under ball weight
4Upgrade shocks if stability at speed is still the issue
5Only then consider heavier springs, and only if load is permanent
6Wheel alignment afterwards, always — ride height changes geometry

Suspension work on the Sunshine Coast

American Truck Centre is at 46 Regent St, Caloundra, and specialises in RAM, Silverado, GMC and Ford F-Series suspension and towing setups. Bring the truck and tell us how you actually use it — we'd rather fit the right shock than the biggest kit. Call 0495 055 559 to talk it through.

Frequently asked questions

Do airbags increase towing capacity?: No. Airbags level the truck and improve how it handles ball weight, but legal towing capacity is set by GVM, GCM, axle limits and towbar rating — none of which suspension changes.
Airbags or heavier springs for towing a caravan?: Airbags for weekend towing, because you keep the factory ride when unhitched. Heavier springs suit trucks carrying permanent weight like a tray, canopy or slide-on camper.
Why does my truck feel unstable at highway speed with the van on?: Most often worn or under-damped shocks, sometimes combined with poor weight distribution. Adding stiffer springs usually makes it worse, not better.
Do I need an alignment after suspension work?: Yes. Any change in ride height alters camber, caster and toe. We align every truck after suspension work — skipping it is how owners end up replacing tyres early.

About the author

Lachlan Matthews — Owner

Lachlan owns American Truck Centre in Caloundra and has spent more than 10 years working on American trucks and full-size US pickups. He oversees every job that comes through the workshop, from logbook servicing and diagnostics to suspension, towing setups and transmission work.

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