JMACX · Adjustable suspension
The shock
The JMACX Alpha 2.5 is a premium, Australian designed and manufactured remote reservoir shock absorber engineered for heavy-duty 4WD touring and towing.
Unlike standard off-the-shelf shocks, the Alpha features a true 2.5-inch outer body with a massive 62.5 mm internal bore. This heavy-duty architecture holds a vast volume of oil, preventing damping fade on punishing corrugated outback tracks and keeping your vehicle stable under maximum loads.
The difference
On standard shocks, adjustments are often limited. The Alpha shocks are engineered with a dedicated adjusting mechanism that directly regulates compression, so you feel the difference in ride quality with just a few clicks.
Alpha shocks are a lifetime asset. They are 100% rebuildable by approved service centres, so you never have to throw them away when they wear.
JMACX stands behind its engineering with a standard 2-year / 50,000 km shock warranty. Service your shocks at the recommended 50,000 km interval through an authorised provider and JMACX extends the warranty by a further 1 year or 20,000 km.
In Australia, JMACX suspension systems underpin federally approved GVM and GCM upgrades (such as the Ineos Quartermaster up to 4.5 tonne), are built to VSB14 requirements, and have passed physical robotic stability control (ESC) testing at a total lift of up to 4 inches with 35-inch tyres. Those are Australian approvals and test results — useful engineering evidence, not South African legal facts. A suspension kit fitted here is not automatically a legal GVM upgrade in South Africa; any GVM claim needs its own local homologation.
The game changer
While you can choose a rugged manual option with easy hand-turn dials on the reservoir, the electric in-cab controller option completely redefines off-road control.
By mounting high-torque stepper motors to the shock adjusters, you can dial your ride from soft to firm without leaving the driver's seat. The system features a built-in G-sensor that continuously monitors your vehicle's physical movement — including forward/back pitch, accelerating, heavy braking, and left/right body roll.
When switched to G-Force Active (GA) Mode, the central program unit takes over in real-time. For example:
The system instantly stiffens the front-left shock and softens the rear-right shock to eliminate body roll.
It firms the front suspension to eliminate nose-diving.
Switch back to Manual Mode in seconds to allow the axles to articulate freely, keeping the cabin flat, comfortable and controlled.
Specification
Open the diagram to view the construction and service components full size.
Choose your option
| Manual adjusters | Electric in-cab (GA) | |
|---|---|---|
| Adjustment method | Hand-turn dial on the reservoir | In-cab dash controller and stepper motors |
| Compression stages | 32 stages | 16 highly distinct stages |
| Adjust from | At the shock, no tools or force required | The driver's seat, while moving |
| Automatic response | Manual selection only | G-Force Active mode reacts in real time |
| Fail-safe | Setting stays where you left it | Motors lock and hold the last active setting |
Tell us your vehicle, permanent load and intended use. We will help specify the appropriate Alpha setup before installation.
