Travelling to the best parts of Australia, you will need to enjoy the ride... literally. Air suspension on offroad camper trailers and caravans is just the easiest way to do this.
One of the benefits of air suspension is adjusting the ride height for different conditions. Later in this article you can see a short video clip of the air suspension on a Kimberley Kamper Platinum model set at three different heights. Setting the suspension low while on the main highways pulls the unit close to the road with improved fuel consumption. More importantly, it is just easier to tow.
When travelling through water crossings or difficult terrain, you can increase the height significantly without an impact on ride quality.
If you are travelling with the maximum water capacity that can be carried on board, the tare weight of just over a tonne will increase by 210kgs. With air suspension, you can lift the height to compensate for added weight.
There is a good reason why computer delivery vans have air-suspension. The soft ride internally protects the valuable goods on board. And this is only around city roads. So when travelling on country roads, air suspension will let your unit glide over the rough and protect your food and belongings.
Have you ever followed a caravan that is jumping all over a corrugated roads at 30-40klms/hr? Is it the suspension, the weight, or just a shocking road? Probably all three!
Most offroad caravans with coil or leaf spring suspension have the dimmema of increasing the stiffness of the springs to carry a higher weight; yet it is softer springs that give better ride control. Large tandem caravans with ATM's over 3 tonne will have to use very stiff springs because of the weight. Then, in certain conditions, you may be towing a kangaroo!
Although the solution has to be a lighter caravan or camper trailer, carrying large water loads gives a wide weight range for the coil or leaf springs. And this means they are difficult to tune.
It helps if your chassis is designed for air suspension.
These are key requirements:
- Independent trailing arm suspension of course
- As there is little "rebound" on air suspension at low air-bag pressures, you do need anti-sway bars on the larger caravans. These can be disconnected if needed.
- High quality shock absorbers: at least mono-tube design (be aware of the myth of have dual shock absorbers)
- Exact braking control so that each wheel, especially on a tandem caravan, has the same braking forces. This requires disc brakes and an electronic boost conroller on the caravan. Without this, in sharp braking, there will be induced swaying.
- A chassis that is flexible yet incredibly strong. Kimberley have a 5 year transferrable warranty to back their design and quality
- Alloy construction for longer life and better securing to independent suspension
- Internal "bump stop" so that if there is a leak, you can limp home on these
- graduated shape gives a variable spring rate depending on position of inflation
- purpose built for off road towable caravans and campers trailers rather than applying a car product (towables can have three times the inertia energy because of the pendulum effect - cars dont have that)
- Low height position: 40mm over bump stop, pressure at 40psi
- Medium height position: 65mm over bump stop, pressure at 44psi
- High position: 100mm over bump stop, pressure at 47psi
Become well informed and download our Open Reasearch book on suspension design.