Ineos Grenadier Air Suspension Conversion
The Ineos Grenadier has earned its place as the spiritual successor to the classic Land Rover Defender — engineered without compromise for those who demand genuine off-road capability without sacrificing daily usability. But even the Grenadier has its limitations. Under load — whether towing, carrying heavy equipment or running a fully kitted-out expedition setup — the standard coil suspension allows the rear to sag, affecting ride quality, handling stability and approach angles. At On Air Suspension, we've designed a full air suspension conversion that solves this and takes the Grenadier's capability to another level entirely.
What Is the Grenadier Air Suspension Conversion?
Our in-house designed air suspension kit replaces the Grenadier's standard coil suspension with a fully adjustable air system, giving you on-demand control over ride height at the touch of a button. Available as a full 4-corner conversion or rear-only kit, the system is engineered specifically for the Grenadier's chassis geometry — not adapted from another platform.
Our in-house designed air suspension kit replaces the Grenadier's standard coil suspension with an air-spring system engineered specifically for the Grenadier's chassis geometry — not adapted from another platform. It's available as a rear-only conversion or a full 4-corner conversion: the rear kit holds the rear at a set ride height automatically under load, while the 4-corner kit adds driver-selectable ride height at all four corners.
What's Included?
Every component in the kit is selected and in many cases manufactured specifically for the Grenadier. Key components include:
- Bespoke On Air / SABO air springs with heavy duty solid pistons — matched to Grenadier suspension geometry
- AMK OAA S1 compressor — the same premium low-noise, low-vibration unit used in our Defender conversion
- Stainless steel height sensor brackets — corrosion resistant for long-term reliability
- Grenadier-specific rear chassis to compressor bracket and mid tank mounting with reinforcement
- On Air Active S1.1 control system — ECU-managed automatic rear levelling from a single height sensor, plus a dashboard dump switch for full deflation at loading height
- Grenadier-specific bump stops and top brackets
- All fixings, nylon tubing, fittings and hardware included
On Air Active — Advanced Air Suspension Control System, included as standard
The rear conversion ships with On Air Active, our own electronic control system — it's included as standard, not an add-on. An ECU reads a single height sensor on the rear axle and adjusts the air springs to hold the rear at a set ride height as load changes. It runs as a standalone system, independent of the vehicle's electronics, with a built-in adjustment delay so it settles to load rather than reacting to every bump or short stop. A dashboard dump switch deflates the rear fully for low-access loading; ride height returns automatically once you drive off.
[Learn more about On Air Active ]
Benefits
- Adjustable ride height* — Lower for easy cabin access, raise for maximum off-road clearance
- Improved on-road ride quality — Air springs absorb road noise and vibration more effectively than standard coils
- Automatic load levelling — Maintain constant ride height regardless of load** — ideal for towing or carrying heavy equipment
- Eliminates loaded rear sag — No drop in ride height when the vehicle is loaded, towing or carrying heavy gear
- Increased off-road clearance* — Raise the vehicle beyond standard height when the terrain demands it
- Improved stability and handling — Optimised suspension geometry under all load conditions — particularly under load where standard coils compromise handling
- Constant ride height under load — **No sagging under payload up to the vehicle's GVW
*Features available with 4-corner system
Is Rear Sag a Problem on Your Grenadier?
If your Grenadier sits noticeably lower at the rear when loaded — whether towing a trailer, carrying a roof tent and expedition gear, or running heavy accessories — the standard coil suspension is working against you. Rear sag reduces ground clearance at the rear, affects approach and departure angles, and alters handling balance. Our rear air suspension conversion eliminates this entirely, maintaining the correct ride height regardless of what you're carrying. The air springs replace the coils and work automatically to keep the vehicle level — you can also adjust height manually at the touch of a button.
Designed and Built in the UK
Every On Air Suspension kit begins on our CAD systems. Our in-house engineering team designs each solution from scratch, prototypes using advanced 3D printing, and validates through physical installation and testing at our Ongar, Essex workshop before a kit ever reaches a customer. Brackets and structural components are manufactured to our specifications by trusted UK suppliers. We don't fit other people's kits — we build our own.
Kit Options
SKU Configuration AKF1250Z Ineos Grenadier 4-Corner Full Air Suspension AKF1751Z Ineos Grenadier Rear Air Suspension Fitting
We offer a full fitting service from our workshop in Ongar, Essex. Call us on 01277 552030 to discuss your requirements.
FAQ
Should I choose the rear-only kit or the 4-corner conversion?
For load-carrying and towing, the rear-only kit (AKF1751Z) covers most Grenadiers. The loads that change ride height — towing, rear-mounted equipment, expedition gear — act on the rear axle, and the rear kit holds ride height under exactly those loads. It includes our On Air Active control system as standard: an ECU levels the rear automatically from a single height sensor, with a dump switch for low-access loading. The 4-corner conversion (AKF1250Z) adds driver-selectable ride height at all four corners — lowering for cabin access, raising for ground clearance, and levelling under uneven loads. If you're unsure, call us and describe how the vehicle is used.
Does the rear kit include a control system, or is that an extra?
Yes — the rear conversion includes On Air Active, our own control system, as standard; it isn't a separate purchase. An ECU reads a single rear height sensor and adjusts the air springs to hold the rear at a set height as load changes, and a dashboard dump switch deflates the rear fully for loading. It runs independently of the vehicle's electronics.Does the kit help when towing? Yes — this is the rear kit's core use case. Towing places nose weight on the rear axle, compressing the standard coils and dropping the rear.
Does the kit increase my Grenadier's payload or towing capacity?
No. The kit manages how the vehicle carries its rated load — maintaining ride height up to the vehicle's GVW. The plated payload, GVW and towing limits are unchanged.
Is anyone else making an air suspension conversion for the Grenadier?
On Air Suspension designed and built the first air suspension conversion for the Grenadier platform, and remains the leading specialist for it. The rest of the aftermarket offers coil and damper upgrades rather than air conversions.
Does the kit fit the Quartermaster as well as the Station Wagon?
Yes — the conversion is available for both the Grenadier Station Wagon and the Quartermaster pickup, with dedicated kit variants for petrol and diesel models. Contact us with your vehicle details and we'll confirm the correct kit.
How long does fitting take?
Fitting is carried out at our Ongar, Essex workshop. The rear conversion typically takes 2–3 days; the full 4-corner conversion 3–4 days. Call 01277 552030 to book or discuss.