Isuzu NPS 4X4 Suspension Upgrades – Read this before you spend anything.

The Isuzu NPS 4×4 is a popular choice for off-road enthusiasts, remote tour operators, and overlanders looking for a rugged, capable truck. However, its factory suspension can struggle under heavy loads, rough terrain, and prolonged use. If you’re considering a suspension upgrade for your NPS, this must-read list will help you make an informed decision.

1. Must-Do Upgrade: Heavy-Duty Shock Mounts

One of the most critical upgrades for the Isuzu NPS is installing heavy-duty shock mounts. The standard factory mounts are prone to failure under heavy loads, off-road driving, corrugated roads, and towing. If these mounts fail, it can lead to costly repairs and potentially leave you stranded on the side of the road or out in the bush. Before you do anything, upgrading to reinforced heavy-duty shock mounts significantly improves durability and reliability, ensuring your suspension system can handle tough conditions without breaking. (Estimated Cost: $500 – $1,500 for parts and installation)

When you consider the high costs of installing upgraded suspension systems this upgrade is a small investment and insurance policy that you are far less likely to experience a suspension failure at the worst possible time.

These fully engineered kits can be purchased for as little as $480-680 AUD (excluding installation) and include skid plates to protect the bottom of the shocks.

Broken Isuzu NPS Shock Mount Failure — Pictured: Factory shock tearing welds off the rear diff. Kings Rubber bush shock tearing mount in half. Kings Remote Res shock with hiem joint snapping the pin off.

Pictured: Upgraded rear shock mounts with protective skids to protect shocks from rocks and striking the ground.

2. Understanding the Limitations of Stock Isuzu NPS Suspension

The stock suspension on the Isuzu NPS is designed for general commercial use but is harsh and unforgiving on rough roads. Common issues include:

Stiff ride quality
Limited articulation off-road due to limited clearance between springs and bump stops.
Reduced comfort under heavy loads
Premature wear or failure of components due to excessive vibrations

3. Choosing the Right Suspension Upgrade

There are multiple upgrade options depending on your needs. The main upgrades include:

Heavy Duty Off-Road Springs – Increased ground and chassis clearance, better articulation compared to the factory setup, along with improved ride quality and superior strength particularly under heavy loads and off road. These will also help to reduce suspension sag when fully loaded. There’s two options when it comes to heavy duty springs for the Isuzu NPS, parabolic and conventional heavy duty leaf springs. Parabolic leaf springs, with their tapered design and fewer leaves, offer a smoother and quieter ride, ideal for mixed-use scenarios that demand comfort with equivalent load capacity. Conversely, conventional springs available in various stiffness for different load ranges, are tailored for specific heavier load-bearing needs and higher durability. (Estimated Cost: $3,000 – $6,000)

Airbag Suspension Helpers – These kits are designed to supplement the existing springs and shocks. Allowing for adjustable ride height and load management. Another advantage of airbag helpers is that the pressures can be increased or decreased for certain terrains or loads which provides some adjustability to These kits are typically not a replacement for existing shock absorbers. Costs range depending on whether you want to have in cab control of pressures using an onboard compressor or whether you are happy to manually inflate/deflate the bags using an external compressor. (Estimated Cost: $2,500 – $5,500)

Isuzu NPS Suspension — Photo credit: Airbag Man Australia

Shock Absorber Upgrades – Heavy-duty shocks improve dampening and handling over rough terrain. (Estimated Cost: $1,500 – $4,000)

Regular Heavy-Duty Shocks – These provide significant improvement over stock shocks with better durability and performance. Typically available in adjustable and non-adjustable. (Estimated Cost: $1,500 – $3,000)
- Advantages: More affordable, easier to install, low maintenance, reliable for general off-road and heavy-load use.
- Disadvantages: Can overheat on prolonged rough terrain, less effective in extreme conditions compared to remote reservoir shocks.
Remote Reservoir Shocks – Designed for extreme off-road use, these shocks have an external reservoir to dissipate heat more effectively. Most remote res shocks are adjustable for different terrain (Estimated Cost: $3,000 – $6,000)
- Advantages: Superior heat dissipation, better performance over prolonged rough terrain, increased lifespan under heavy use.
- Disadvantages: More expensive, requires more maintenance, may need professional installation.

King Remote Reservoir Shocks. Photo credit: Mike’s Shock Shop

4. Top Suspension Brands to Consider

If you’re looking for tried-and-tested solutions, here are some reputable brands:

Airbag Man – Manufacturer of airbag helper kits for the Isuzu NPS 4×4 airbagman.com.au
King Shocks – Full suspension kits, springs and shocks mikesshocks.com/product/isuzu-nps-kit
Dobinsons – Manufacturer of springs and shocks dobinsons.com
All Terrain Warriors – Full suspension kits allterrainwarriors.com.au
Suspension Supplies Australia – Full suspension kits, springs and shocks ssa.com.au
EFS 4WD – Manufacturer of springs and shocks efs4wd.com.au

5. Installation Considerations

Before upgrading your suspension, consider the following:

Professional Installation vs. DIY – Some upgrades, such as shock replacements, can be done at home, while full conversions may require expert fitting. (Estimated Labor Cost: $500 – $5,000)
Compliance – Ensure modifications comply with local regulations, especially regarding ride height and weight ratings.
Additional Modifications – A new suspension setup may require upgrades to steering components, sway bars, or brake lines.

6. Performance & Longevity: What to Expect

After upgrading your suspension, you can expect:

A smoother, more comfortable ride, especially on corrugated roads.
Improved handling and stability under heavy loads.
Reduced strain on other components, leading to a longer vehicle lifespan.
Better off-road articulation and traction.

Is it worth upgrading Isuzu NPS Suspension?

Upgrading your Isuzu NPS suspension is one of the best modifications you can make for improved comfort, durability, and off-road capability. If you are doing heavy off-road use, overlanding, touring or towing heavy loads upgrading your suspension is highly recommended to also reduce the risk of breaking suspension components and leaving you off the road or ending up having to replace broken suspension components down the track.