Why You Want One. An air suspension offers at least five major benefits:
Tunability: Air suspensions have a wide tuning range for spring rate and load capacity. Weeks of conventional spring and shock tuning can be painlessly compressed into a few minutes via in-car adjustability. Getting the ride height, load, and rate on a coil spring right on the first try is a hit-and-miss affair, but an air suspension provides a much broader envelope, so precise selection isn't as critical as on a conventional spring.
Handling: Most air springs are progressive. The more they compress, the stiffer they get. Combine this inherent progressive spring rate with in-car adjustability, and the result is enormous performance potential. Tuning for conditions is quicker and faster. In a sophisticated handling application, the air spring should be coupled with shocks adjustable for both rebound and compression and carefully selected antisway bars.
Performance customization: Everyone has his own personal idea of how his truck should ride and handle. With an air suspension, these wishes can be accommodated with little or no component changes. By adjusting air pressure and shock valving, you can make the same car be soft and comfortable, firm and tight . . . or anywhere in between. You can drive the car comfortably to the track, firm up the air pressure and shock valving to go racing, then readjust the pressure and valving to return home in comfort.
Stance: Air suspensions make it easy to lower the truck so you can look cool. At the far end of the coolness spectrum are spark-throwing minitrucks and lowriders, but today, they represent only a small segment of the market. Far more typical is the guy who just wants to lower his car or truck a reasonable amount for better looks without sacrificing any driveability or durability. Most kits come set up to deliver a normal ride height that's several inches lower than the stock springs. Regardless of how low the car is, air suspensions make it easy to raise the car back up for normal cruising, getting into gas stations, or even rolling onto the trailer.
Load carrying: This is the original commercial application for air suspensions: helping 18-wheelers carry heavy loads while improving driver comfort. Although probably not the main reason for switching over on a c10 truck , it definitely is one solution for making your dualie tow truck more driveable under varying-load conditions. In fact, some new SUVs now come with air suspensions.
Over the last decade or so air suspension has become extremely popular in the custom automobile culture: street rods, trucks, cars, and even motorcycles may have air springs. They are used in these applications to provide an adjustable suspension which allows vehicles to sit extremely low, yet be able rise to a level high enough to maneuver over obstacles and inconsistencies in the roadways (and parking lots). These systems generally employ small, electric or engine-driven air compressors which sometimes fill an on-board air receiver tank which stores compressed air for use in the future without delay. High-pressured industrial gas bottles (such as nitrogen or carbon dioxide tanks used to store shielding gases for welding) are sometimes used in more radical air suspension setups.