RV Education
RV Resources and Tech Advice
Mike Wilson is a RVDA Certified Master RV
Tech. with over 25 years experience and now he's sharing his
knowledge with you.
Mike is the president of Wilson RV
and developer for The RV Help
Desk.
Air Spring Kits
Suspension air springs are rubber bellows that hold air pressure. There are a variety of shapes and sizes available. Air springs are typically inserted inside of coil springs, or between leaf springs and the frame using brackets.
Air springs can be very helpful in leveling and stabilizing a vehicle. There are several manufacturers. Kits vary depending on the application. A kit consists of air bellows, lines, brackets, and hardware. Air springs can be used on the front or rear of a vehicle. The design of the air spring depends on the application. Kits are available to fit most vehicles.
There are several benefits to using air springs to level a vehicle over other methods.
1. The ride can
be the same as stock with the air springs set at the minimum air
pressure
2. The original ride height can be maintained with the minimum air
pressure
3. Air lines can be separated for vehicles with a side to side
imbalance
On board air compressors can be added to the system to make adjustment easy. The compressor runs from the vehicle battery. It is controlled from a panel with switches and gauges located near the driver. A single system uses one switch and one gauge. It simply adds or releases air to a pair of air springs. A dual system uses two switches and two gauges. It will adjust air pressure separately from side to side or front to rear. As many as four switches and gauges can be used to adjust side to side and front to rear.
Installation can be accomplished by anyone with some basic mechanical knowledge. The first step is to create a plan. You first need to know what you want the air springs to do. You will need to know if you want front, rear, or both. Rear only will level and stabilize. Front will increase the stabilization. A heavy vehicle such as a class A RV can benefit from front stabilization. The rocking motion felt while driving can be significantly reduced using front and rear air springs. Some RV chassis have air springs installed from the factory as original equipment (Chevrolet/ Workhorse P30, P32 Chassis). This style air spring is different than an add on style. The original equipment air spring fills the space between the coils in the front springs. It is meant to stabilize the suspension to eliminate rocking motion. The problem is, the air spring cannot lift, and it can only fill space. There is also an issue with longevity. These type air springs tend to rub on the coils and deteriorate. The air should be added only with the weight off the suspension so the air spring can fill the coil without tearing.
Once the plan is made, the air springs can be purchased and installed. Read all directions prior to starting the installation. The vehicle will need to be raised and properly supported for safety. If your vehicle is too large or you don’t have the proper equipment to raise it safely, take it to a professional. After the vehicle is supported the installation can begin. Leaf spring vehicles will have brackets that need to be attached. In most cases there will be frame holes in place that will be utilized. The air springs will fit between the frame and axle in the brackets. Air lines will be routed to a location where they can be easily filled or to a control panel inside if being installed. Coil springs use a bellow that goes inside the spring. Unlike a factory bellow that fill coil gaps, the bellow will actually lift the vehicle by extending between the frame and axle.
After installation be certain to follow the manufacturer’s guidelines for minimum and maximum air pressure. It is important to follow the minimum pressure guidelines so the air bellows will not be damaged when leveling or stabilization is not needed. Be certain the bellows and air lines are away from sharp objects and heat. There have been many RV’s with factory installed rear air springs that were installed with exhaust systems routed too close causing failure. In many cases heat shields are included and must be used. In some cases exhaust systems must be modified to provide necessary clearance. In any case, the air springs should be inspected regularly