rising rate self-adjusting digressive working piston one-piece alloy rod guide and seal bilstein patented nitrogen chamber and floating piston bilstein gas shock technology makes steering smooth the bilstein gas pressure shock seals nitrogen gas in a special compartment at better control and stability and operates at a lower temperature than standard chassis and workhorse ifs suspensions through 2004 firestone ride-rite air springs offer added suspension support to light trucks bottoming out and prevents unbalanced loads while increasing ride comfort improving steering control and braking supersteer maintenance-free urethane springs share the load assemblies that cause excessive side-to-side movement patented sumo springs offer enhanced suspension get more responsive steering and eliminate rear axle known as "the tail wagging the dog" rear axle shift causes the front end to steer itself when being passed by other available for most motorhomes exhaust modifications may be required for some vehicles