Abstract: A combination load-leveling and kneeling air suspension system for a vehicle having a sprung member and an unsprung member. The system has a pair of laterally spaced air springs, a pressurized air reservoir with a first tubing line connecting the pressurized air reservoir to the first laterally spaced air spring and a second tubing line connecting the pressurized air reservoir to the second laterally spaced air spring. The first tubing line and the second tubing line have a common tubing portion. A first valve member is located in the first tubing line but not in the common tubing portion. Likewise, a second valve member is located in the second tubing line but not in the common tubing line portion. A third tubing line is connected between the pair of laterally spaced air springs and an isolation valve is located in the third tubing line intermediate its ends. A fourth tubing line connects the isolation valve with the common tubing line portion.

Abstract: A vehicle suspension system with a control valve mechanism for regulating the air pressure within the vehicle's air springs that functions to increase the spring rate when the air spring is being compressed on curves and bumpy road surfaces. The vehicle suspension system would have an axle, a vehicle chassis, an air spring attached between the axle and the chassis, an air reservoir, and a control valve in an air line connecting the air spring and the air reservoir. The control valve has a housing with an air inlet port located in its top wall and an air exit port located in its bottom wall. A cylindrical plug member is mounted within the valve housing and it has a bore hole passing substantially diametrically through it so that when the position of the cylindrical plug within the housing is moved or adjusted the opposite ends of the bore hole can be aligned with both the air intake port and the air exhaust port at the same time.

Abstract: An improved suspension system for a vehicle having a body-supporting frame and a wheel-supported axle. A pair of air spring units are laterally spaced adjacent the opposite ends of the axle. Each of these air spring units has a lower air spring seat, an air spring body, and an upper air spring seat. The lower air spring seat members are attached to the top to the axle. A top mounting plate secures the upper air spring seat members to the frame. The top mounting plates are sloped inwardly such that their inward side lies at a vertical height lower than their outward side. The center of the upper air spring seat members are laterally offset in an inboard direction with respect to the center of the lower spring seat members.