Many vehicles cope fine when empty but with a full touring load or heavy trailer attached, it’s typical for the vehicle’s rear suspension to remain compressed. On-road this can result in floaty steering, headlights pointing skyward and reduced braking ability.
Off-road it means the already partially compressed shock absorbers and coil or leaf suspension has less ability to absorb bumps. In some ways, it’s similar to running shorter shock absorbers; the resulting ride is less comfortable, and the chance of bottoming out the suspension and damaging the vehicle is higher.
Several new, and planned vehicles, including Land Rovers and the Tesla Cyber Truck run or will run, on full air suspension systems. These vehicles use heavy-duty airbags in place of, rather than in support of, coil or leaf suspension.
It’s also possible to retrofit this type of suspension to some vehicles like 200 Series LandCruisers, Defenders and Patrols.
Commonly Airbag Man suspension systems are installed with manual inflation valves. Adjusting these is precisely like changing tyre pressures. It isn’t difficult at all, but there is a more straightforward way, and it’s resulted in us fine-tuning our airbags far more often.
Pneumatic air suspension switches and a dual digital gauge can be retrofitted to most existing systems or purchased as part of the kit for new installs.
The airlines are re-routed to the switches for deflation, and separate lines connect between the compressor and the same switches for inflation. Airbag Man offers a range of options and in our Cruiser, we were able to use the adapter in their Existing Compressor Kit to connect to our ARB Twin Compressor.
We opted to install our air suspension switches and gauge in the rear of the vehicle; with the compressor and airbags nearby, it meant we could keep the airlines short which made the install easier.
It’s possible to fit the controls in the cabin, and Airbag Man also has a wireless controller option.
Typically for us, our most significant loads are on our long and remote trips. Even with only two passengers, with 220 litres of fuel, 100 litres of water, food, camping and recovery gear and the usual build weight of the vehicle we’ll often depart weighing close to our upgraded GVM of 3,660kg.
We have a quality ARB Old Man Emu aftermarket suspension fitted with the rear Airbag Man Suspension assisting the back. To ride level at full weight, we would have needed to upgrade our 600kg constant load rear leaf suspension to the 800kg option. Doing this would have suited our touring trips, but at lighter loads, it would heavy left the vehicle uncomfortable on the road and without flex off-road.
With our system, we switch on our compressor and then use the pneumatic switches to air down or up. Both airbags at once. The airbags fill quickly making the ability to partially press the switches to dial in the correct pressure on the gauge helpful.
To prevent body roll of our 76 Series at highway speeds, we aim to run the rear airbags reasonably firm, regardless of load.
When we are off-roading, we soften the airbags at the same time as we air down. If we are travelling light, we can go low to allow for maximum flex. At heavier loads, we go lower than our highway pressures, and let the load dictate the pressure; softer but so the vehicle still sits level.
Installation by Ultimate 4WD.