Vehicle Compatibility: These SumoSprings are specifically designed to fit your 2017-2025 F250/F350 (4WD Only), ensuring a perfect fit and maximum reliability Progressive Load Support: SumoSprings compress under increasing weight to reduce rear-end sag, improve ride height, and maintain balanced handling No Air, No Maintenance: Made from closed-cell microcellular polyurethane, these springs don’t require airlines, compressors, or constant adjustment Smoother, Safer Handling: The progressive foam design dampens harsh impacts, minimizes body roll and sway, and boosts driver control Built to Last: Weather-resistant polyurethane resists UV, moisture, corrosion, and extreme temperatures — backed by a lifetime warranty