the spring member to an underside of the light duty trailer, an air spring connected between the underside of the light duty trailer and the spring member, and a limiting assembly, preferably a double-hinged spring shackle assembly, for connecting a rear end of the spring member to the underside of the light duty trailer. The front end of the spring member is pivotally connected to the tower. The rear end of the spring member is pivotally connected to the limiting assembly. The axle is connected to the spring member. A shock absorber is provided between the underside of the light duty trailer and the axle. In operation, if no bumps or ruts are encountered, the spring member remains generally horizontal relative to the underside of the light dutytrailer. If one or both of the tires encounter a bump in the road, the rear end of the spring member moves upwardly relative to the underside of the light duty trailer and the air spring and the shock absorber compress. If one or both of the tires encounter a rut in the road, the rear end of the spring member moves downwardly relative to the underside of the light duty trailer and the air spring and the shock absorber expand.