If you're familiar with the typical suspension setup on a small car or truck, you may know that it relies on coil springs and fluid that drives a piston within a strut. Yet the system fitted to a large truck is entirely different, and if you now have responsibility for maintaining such a vehicle, you need to become familiar with air suspension instead. How does this work, and crucially, what can go wrong?
How an Air Suspension System Works
Your heavy-duty vehicle has a rubber airbag between the chassis and the axle on each corner. It's a sturdy device that inflates or deflates according to the vehicle's configuration and the road conditions beneath.
Each bag has a sensor that can accurately record the air within and send a signal to the compressor to pump more in or draw some out. The sensor performs its work with a high degree of accuracy in order to keep the vehicle stable in all situations.
The compressor is generally a motor that maintains air pressure at set levels with a high degree of consistency. The air flows between the compressor and each bag through a network of flexible hoses, with two-way valves allowing air to flow in both directions.
Crucially, there is also a dryer mechanism fitted to the compressor. This will process the air from the surrounding atmosphere before it is delivered to the compressor to get rid of any harmful moisture. If the air was allowed to get into the system, it could cause corrosion and other issues.
You will need to be aware of any problems as soon as they arise and before they can cause any bigger issues. In most situations, the compressor and dryer will function without too much drama, but as those flexible pipes are situated in vulnerable positions, they sometimes begin to deteriorate. The air will start to leak out if they develop any pinholes due to damage. Likewise, the airbags themselves are susceptible to wear, and a leak could also develop here.
When leakage occurs, the airbag closest to the problem area will not inflate properly. You may notice that the vehicle tends to "sag" on that corner, which will certainly affect the overall ride. You may also see that the compressor runs non-stop as it is trying to generate enough air to counteract that leak.
What to Do Next
If you've noticed that your vehicle is not handling correctly or appears to be dealing with a problem in one corner, it's time to take action. When you take your truck in for a full repair, the technician will deal with the pressing matter and give the entire system a once-over.
Reach out to a truck repair shop for more information.