Do airbags make the ride harsh?

Not when set up correctly. Deflated to a low base pressure of around 5–10 psi, airbags barely change the empty ride, which is their main advantage over heavier springs. Problems only arise when bags are left at high pressure all the time, which stiffens the ride unnecessarily and accelerates wear on the bags themselves.

Can I have both airbags and heavy-duty springs?

Yes. Trucks with a permanent tray plus occasional van or caravan towing often run heavier springs as the constant base load support and airbags on top to manage the extra variation when towing. This is a common setup for Sunshine Coast trucks that work during the week and tow on weekends.

Do airbags or springs increase my towing capacity or GVM?

No. Neither option changes your truck's legal GVM, GCM or braked towing capacity — those figures are set by the compliance plate and engineering approval. Load support only manages how the suspension behaves within your existing legal limits. If you need more legal capacity, you need a certified GVM upgrade, not stiffer suspension.

How much does it cost to fit airbags or heavy-duty springs?

Cost depends on the truck, the kit and how it's loaded, so we quote all suspension upgrades on enquiry rather than publish a flat figure. Bring your RAM, Silverado, GMC or F-Series to our Caloundra workshop and we'll assess your setup and provide an accurate quote.

How do I know if my springs are too soft for my load?

Watch for a sagging rear end with everyday gear, headlights pointing upward when loaded, vague steering under load, or uneven rear tyre wear. If these show up with a permanent load rather than only when towing, heavy-duty springs are likely a better fix than airbags alone.

Is it legal to fit airbags or stiffer springs myself?

It's legal to fit either provided the work doesn't push the truck's actual laden weight past its GVM and doesn't compromise ride height, geometry or braking performance. It's not legal to use load support as a way to keep towing or carrying more than your compliance plate allows — that always requires a proper GVM upgrade.

How often should airbags be checked?

We check airbag pressure and condition at every service interval, and recommend an immediate inspection if you notice cracking, chafing or unusual pressure loss. There's no fixed replacement schedule for airbags themselves, but the rubber does perish over time and with UV and heat exposure on the Sunshine Coast.

What's the main downside of heavy-duty springs?

The main downside is that the rate is fixed — a spring stiff enough for a loaded tray and canopy will ride firmer than standard when the truck is empty, since there's no way to soften it for lighter days. That's the main reason occasional towers usually prefer airbags over a permanent spring upgrade.

Airbags vs Heavy Duty Springs for US Trucks

The core difference

A spring is fixed: the rate you choose is the rate you live with, loaded or empty. An airbag is adjustable: you add pressure when you hitch up and let it out when you don't. That single difference decides most cases, and almost every question below comes back to it.

Which is better for towing a caravan?

For a full-size American truck that tows a caravan or boat only some weekends, airbag helper kits are usually the better choice. You run low pressure — often around 5–10 psi — for the drive to Caloundra and back with nothing on the hitch, then pump the bags up to 40–80 psi before you hook up a heavy van. Sacrifice a fixed spring rate stiff enough for towing and you'll feel every joint in the road on the school run.

Which is better for a tray, canopy or permanent tools?

If the weight never comes off — a steel tray, a canopy, a toolbox, a compressor and a permanent load of gear — heavy-duty springs are the more sensible fit. There's nothing to adjust because the load doesn't change, and a spring rated for that constant weight rides better under load than a soft factory spring propped up with high air pressure every day.

	Airbags	HD springs
Occasional caravan or boat	Best choice	Harsh when empty
Permanent tray and canopy	Workable	Best choice
Adjustable per trip	Yes	No
Maintenance	Check pressures, inspect bags	None
Raises legal capacity	No	No
Typical fitment time	Half to full day	Half to full day
Ride when unladen	Excellent if deflated correctly	Firmer than standard

How much does an airbag kit or spring upgrade cost?

As with most suspension work on these trucks, we quote on enquiry once we know your make, model, GVM and how the truck is actually loaded — parts pricing and labour time vary too much between a RAM 2500, a Silverado 1500 and a GMC to publish a single number. Bring the truck to our Regent Street workshop in Caloundra and we'll assess it properly rather than guess over the phone.

Neither option raises GVM. If you're over your legal limit, load support makes the truck feel better while it's still illegal — a certified GVM upgrade is the only real fix.

Is it legal to just fit airbags or stiffer springs?

Fitting either is legal provided the work doesn't push the truck's actual laden weight past its GVM, and provided ride height, geometry and braking aren't compromised. What's not legal is treating load support as a substitute for a proper GVM upgrade. Airbags and springs manage how the suspension behaves under a given weight — they don't change what weight the compliance plate allows. If your loaded truck already sits near or over GVM, load support hides the symptom, not the overload.

What happens if you only fit one when you needed both?

Springs sized for a permanent tray but no towing will still sag under a heavy caravan's ball weight, because the increase in constant load and the occasional spike from towing are different problems. Airbags fitted to a truck that's already sagging under a permanent overload just mask the sag with air pressure — the springs are still doing less work than they should, and ride quality and handling suffer. That's why plenty of Sunshine Coast tourers with a tray, canopy and a caravan end up running heavier springs as the base and airbags on top for the towing spike.

Symptoms that suggest your current setup is wrong

Rear end sags noticeably with everyday gear, not just towing
Headlights point skyward when loaded
Steering feels vague or wanders under load
Harsh, jarring ride when the truck is empty
Uneven tyre wear across the rear axle
Brake pedal feels longer or softer when heavily loaded

How often do airbags need to be checked or serviced?

We recommend a pressure and visual check at every service interval — a quick job we build into minor and major services for towing trucks. Airbags themselves have no scheduled replacement, but rubber perishes, so any cracking, chafing against brackets or slow pressure loss should be inspected immediately rather than left until a bag fails on the road.

Check item	Frequency
Bag pressure (loaded and unloaded)	Every service, or before/after each big tow
Visual inspection for cracking/chafing	Every service
Line and fitting check for leaks	Every service
Spring condition and ride height	Every 12 months or if ride height changes

Doing it properly

Independent left/right control if you load unevenly
Minimum 5 psi in the bags at all times to prevent chafing
Clearance checked to brake lines, exhaust and bump stops
Alignment checked afterwards if ride height changed
Documented loaded and unloaded pressures for your setup

Can you run airbags and heavy-duty springs together?

Yes, and for a truck that's both a daily worker and a weekend tow rig, running both is common. Heavy-duty springs carry the permanent load — the tray, canopy and tools — while airbags take up the extra variation when a caravan or trailer is hitched on top. We set these up together on plenty of Sunshine Coast RAMs and Silverados that work during the week and tow on weekends.

Where to get it assessed on the Sunshine Coast

American Truck Centre in Caloundra works exclusively on full-size American pickups — RAM, Chevrolet Silverado, GMC and Ford F-Series — so we see this exact decision constantly. Bring in your truck, tell us how you load and tow it, and we'll recommend airbags, springs, both, or point you toward a GVM upgrade if that's what the numbers actually call for. Call us on 07 5491 2199 or drop into 46 Regent St, Caloundra QLD 4551.

Frequently asked questions

Do airbags make the ride harsh?: Not when set up correctly. Deflated to a low base pressure of around 5–10 psi, airbags barely change the empty ride, which is their main advantage over heavier springs. Problems only arise when bags are left at high pressure all the time, which stiffens the ride unnecessarily and accelerates wear on the bags themselves.
Can I have both airbags and heavy-duty springs?: Yes. Trucks with a permanent tray plus occasional van or caravan towing often run heavier springs as the constant base load support and airbags on top to manage the extra variation when towing. This is a common setup for Sunshine Coast trucks that work during the week and tow on weekends.
Do airbags or springs increase my towing capacity or GVM?: No. Neither option changes your truck's legal GVM, GCM or braked towing capacity — those figures are set by the compliance plate and engineering approval. Load support only manages how the suspension behaves within your existing legal limits. If you need more legal capacity, you need a certified GVM upgrade, not stiffer suspension.
How much does it cost to fit airbags or heavy-duty springs?: Cost depends on the truck, the kit and how it's loaded, so we quote all suspension upgrades on enquiry rather than publish a flat figure. Bring your RAM, Silverado, GMC or F-Series to our Caloundra workshop and we'll assess your setup and provide an accurate quote.
How do I know if my springs are too soft for my load?: Watch for a sagging rear end with everyday gear, headlights pointing upward when loaded, vague steering under load, or uneven rear tyre wear. If these show up with a permanent load rather than only when towing, heavy-duty springs are likely a better fix than airbags alone.
Is it legal to fit airbags or stiffer springs myself?: It's legal to fit either provided the work doesn't push the truck's actual laden weight past its GVM and doesn't compromise ride height, geometry or braking performance. It's not legal to use load support as a way to keep towing or carrying more than your compliance plate allows — that always requires a proper GVM upgrade.
How often should airbags be checked?: We check airbag pressure and condition at every service interval, and recommend an immediate inspection if you notice cracking, chafing or unusual pressure loss. There's no fixed replacement schedule for airbags themselves, but the rubber does perish over time and with UV and heat exposure on the Sunshine Coast.
What's the main downside of heavy-duty springs?: The main downside is that the rate is fixed — a spring stiff enough for a loaded tray and canopy will ride firmer than standard when the truck is empty, since there's no way to soften it for lighter days. That's the main reason occasional towers usually prefer airbags over a permanent spring upgrade.

Airbags & Load Support Suspension & Lift Kits

Airbags vs Heavy-Duty Springs: Which Does Your Truck Actually Need?