Eliminate your spacer leveling kit and install something that actually improves the ride in your Ford SuperDuty. Designed with heavy duty truck use in mind, this spring provides rugged load handling capabilities while maintaining an extremely comfortable ride. Kryptonite's true Dual Rate spring can provide the best of both worlds. Using top rated materials, Kryptonite has produced a plush ride with minimal spring sag. Mile after mile Kryptonit's springs will hold up to any truck, and any job.