A Nissan NV350 Urvan sitting low at the back after a full day of parcel runs or a ute full of trade gear is a suspension support problem, not something to shrug off. This guide covers what a load assist airbag kit actually does for a leaf-sprung van, what to check before you buy one, and how to confirm the right fit for your NV350 Urvan.
- A nissan nv350 urvan load assist kit works with the existing rear leaf springs, not instead of them.
- Confirm exact NV350 fitment through Boss Air Suspension's application guide before ordering anything.
- Comparable Boss kits for Toyota HiAce and Mercedes Sprinter vans in 2026 run from roughly $745 to $865, giving a realistic price benchmark.
- Skip universal clamp-on airbags that ignore your NV350's specific chassis mounting points.
Why this matters
The NV350 Urvan rides on rear leaf springs, same as most one-tonne commercial vans. Load it with parcels, tools, or a rooftop conversion and the back end drops, the headlights point skyward, and the steering gets light. That's normal leaf spring behaviour under load, not a fault.
A load assist airbag kit adds adjustable air support inside the existing leaf spring pack. It doesn't replace the springs and it doesn't increase your van's legal GVM or payload rating — it helps the suspension you already have carry a load more evenly. If you're weighing up options, start with how to choose the right load assist airbag kit before you commit to a specific kit.
Who this is for
This guide is for NV350 Urvan owners running the van hard: courier and last-mile delivery drivers, tradies carrying tools and materials daily, and anyone converting an NV350 into a campervan or mobile workshop. If your van sags noticeably with a full load, sways under braking, or the tail drops on a boat ramp or steep driveway, keep reading.
What to look for in a load assist kit for the NV350 Urvan
Vehicle-specific mounting, not universal clamps
A kit designed around the NV350's actual chassis rail and axle geometry sits correctly and stays put. Universal clamp-on kits are a compromise — they're built to fit many vans loosely rather than one van precisely, which shows up as rattles, uneven bellow wear, or brackets working loose over time.
Bellow capacity matched to rear axle load
The airbag has to suit the weight the NV350 typically carries, not just squeeze into the available space. A double bellow airbag design spreads load over a larger surface than a single bellow, which matters when the van is regularly near its rated capacity.
Adjustable air pressure for variable loads
A courier run half full and a campervan conversion loaded for a week away put very different weight on the rear axle. Air pressure you can adjust by hand or through a digital controller lets you dial in support for the load you're actually carrying that day, rather than running one fixed setting all the time.
Compatible with the existing leaf springs
Load assist is designed to work with your leaf springs, not against them. Anything marketed as a spring "replacement" or an unapproved GVM fix for a van needs scrutiny — Boss Air Suspension's kits are load assist, and any GVM-related claim needs to be backed by the actual product documentation.
Air line, fittings and warranty support
Cheap push-fit airline and unbranded fittings are a common failure point on DIY-grade kits. Quality fittings, a proper mounting hardware set, and a five-year warranty on the airbags themselves are what separate a kit built for daily commercial use from a budget import.
How comparable Boss Air Suspension van kits are built
There's no confirmed NV350 Urvan-specific kit listed at the time of writing, so the fastest way to judge quality is to look at how Boss Air Suspension approaches other leaf-sprung and FWD commercial vans already in the range. These aren't picks for your NV350 — they're the benchmark for what a properly engineered van kit looks like.
Toyota HiAce Load Assist Kit — the closest cousin on sale. The HiAce runs a comparable rear leaf-spring layout carrying courier and trade loads across Australia daily. Verdict: Skip for direct NV350 fitment since the brackets are HiAce-specific, but it's a solid reference for load assist airbags built for the Toyota HiAce.
Mercedes Sprinter / VW Crafter Load Assist Kit — the FWD European benchmark, priced at $865.00 in 2026. It's designed for a specific ride height window, which shows the level of vehicle-specific engineering Boss applies across the van range. Verdict: Skip for direct fitment, but check the load assist kit for Mercedes Sprinter vans for a realistic price and spec comparison.
Ford Transit Load Assist Kit — built for another high-volume courier van platform. Its bracket set and bellow sizing are matched to the Transit's own chassis points, not adapted from something else. Verdict: Skip for the NV350, but it confirms Boss extends proper vehicle-specific engineering across mainstream commercial vans, not just utes and 4WDs.
For an actual NV350 Urvan, the correct move is confirming fitment directly — through the vehicle application guide or by contacting Boss Air Suspension — rather than assuming a kit built for a different van will bolt straight on.
What to avoid
- Universal U-bolt or clamp-style airbag kits advertised as fitting "most vans." They're rarely matched to the NV350's specific axle and chassis dimensions and tend to shift under load.
- Any kit marketed as increasing your GVM or payload rating. Load assist airbags support the existing suspension — they don't change your van's legal rating unless it's a documented, approved GVM upgrade.
- Unbranded airline and fittings sold separately to save money. They're the most common failure point reported on DIY van installs, well before the airbags themselves wear out.
Verdict comparison
| Platform | Drivetrain | Rear support challenge | Confirmed Boss fitment | Verdict |
|---|---|---|---|---|
| Toyota HiAce | FWD, leaf-sprung rear | Courier/trade sag | Yes | Buy (HiAce owners) |
| Mercedes Sprinter / VW Crafter | FWD, leaf-sprung rear | Panel van load sag | Yes | Buy (Sprinter/Crafter owners) |
| Ford Transit | FWD, leaf-sprung rear | Courier van sag | Yes | Buy (Transit owners) |
| Nissan NV350 Urvan | RWD, leaf-sprung rear | Courier/trade/conversion sag | Confirm via application guide | Confirm before buying |
Where to source a kit
- Confirm your NV350 Urvan's exact model year and rear suspension type before contacting Boss Air Suspension for fitment advice.
- Buy the full kit — airbags, brackets, air line and fittings — as a matched set rather than mixing components from different suppliers.
- Ask about the five-year warranty coverage on the airbags specifically, since warranty terms can vary by component.
FAQ
Does Boss Air Suspension make a load assist kit for the Nissan NV350 Urvan?
Fitment for the NV350 Urvan needs to be confirmed directly with Boss Air Suspension or through the vehicle application guide, since it isn't listed as a confirmed application at the time of writing. Contacting Boss before you buy avoids ordering the wrong bracket set.
Will a load assist airbag kit increase my NV350's GVM or payload rating?
No, a standard load assist kit does not increase your van's legal GVM or payload rating. It supports the existing rear leaf springs under load; only a documented, approved GVM upgrade changes the legal rating.
How much does a load assist kit cost in 2026?
Comparable Boss Air Suspension van kits run from around $745.00 to $865.00 in 2026, depending on the vehicle and bracket set required. Exact NV350 pricing depends on confirmed fitment.
Can I install a load assist airbag kit myself?
Many load assist kits are designed as a bolt-on install using the factory mounting points, and can be fitted with basic tools by a competent DIYer or a workshop. If you're unsure about torque settings or air line routing, a suspension specialist can fit it faster and confirm everything is sealed correctly.
Is load assist suspension legal in Australia?
Yes, load assist airbag kits that work with the vehicle's existing suspension and don't alter its GVM are a standard, legal accessory across Australia. Always check local requirements if you're combining load assist with other suspension modifications.
What's the difference between load assist and a full air suspension kit?
Load assist airbags support the existing leaf springs and only add capacity when inflated, while a full air suspension kit typically replaces the spring as the primary load-bearing component. Vans like the NV350 Urvan generally use load assist rather than full replacement systems.
How do I know if my NV350 Urvan needs load assist airbags?
Visible rear-end sag under a full load, headlights pointing upward, or reduced steering feel while loaded are the clearest signs. If the van sits noticeably lower at the back with parcels, tools, or camper fit-out weight aboard, load assist is worth investigating.
Does a load assist kit affect ride quality when the van is empty?
Air pressure is adjustable, so you can run lower pressure for an empty or lightly loaded van and increase it when carrying weight. This keeps ride quality reasonable across both conditions rather than locking you into one fixed setting.
One last thing
The number that trips up most van owners isn't the price of the kit — it's the mounting bracket. A kit engineered for the wrong chassis point on a leaf-sprung van like the NV350 Urvan will still bolt on somewhere, it just won't sit level or last. Confirm fitment before you buy, not after.
