An air spring having a relatively low and a relatively high spring height includes a retainer, a base housing, an elastomeric sleeve secured to the retainer at a first end and secured to the base housing at a lower end to form a chamber, the elastomeric sleeve expanding from a relatively collapsed configuration at the low air spring height into an expanded configuration at the high air spring height. A confined bladder is disposed within the chamber, the bladder being inflatable to displace a variable portion of an expanded volume within the sleeve chamber at the high air spring height. The spring rate of the air spring is adjusted by an adjustment to the volume of air displaced by the inflated bladder within the sleeve chamber and by overpressurizing the bladder relative to the air spring sleeve, whereby the air spring is adapted to provide a relatively low spring rate at the lower height and a relatively high spring rate at the higher height.