SuperSprings Helper Spring Kit SSA24 for the Chevy Silverado, Express, GMC Sierra, Savana, Dodge Ram 2500, 3500, 4500, 5500, Ford F-350, F-450 Super Duty improve driver control by drastically reducing sag and sway while maintaining a nice, smooth ride. SuperSprings work in conjunction with the factory spring pack and adjust automatically to accommodate different load and road conditions.