Abstract: The auxiliary suspension device is relatively neutral at rest and responds in coordination with the existing suspension system upon application of a load. The redundant suspension device has an inflatable bellow that is mounted between a vehicle's frame and an existing vehicle suspension element.

Abstract: A suspension strut including an air spring unit and a damper unit that are aligned on a common axis is disclosed. The air spring unit includes a rolling tube having a flared terminal end that extends over a damper tube associated with the damper unit. The damper tube has a circumferential groove formed in an outer diameter of the damper tube. A retaining ring has a greater outer diameter than the outer diameter of the damper tube and is positioned in the circumferential groove. A base has an inner diameter less than the outer diameter of the retaining ring, and an outer diameter smaller than the predetermined diameter of the flared free end, and is supported on the retaining ring. A torsion element fits around the damper tube and within the flared free end.