Carli Suspension Ford 2.5" t0 5.5″ Lift Springs for the 2005+ Super Duty Platform. Carli springs are Shot Peened and Pre-Set, then powder coated by the manufacturer ensuring they won’t sag and the finish will last for years to come. The 2.5″-3.5" Lift Springs are a linear spring with a slightly softer rate than stock to provide a leveled stance and smooth ride through the whole travel stroke. The 4.5″-5.5" springs are side specific and multi-rate to provide ride comfort and a secondary increased spring rate to prevent the suspension from hitting the bump stops in their massive travel range. SKU: CS-FLC-05 Fitment: 2020+ F250/350 4x4, Diesel - 3.5" of lift Fitment: 2005-19 F250/350 4x4, Diesel - 2.5" of lift Linear Rate Spring Shot peened & Pre-set for Maximum Durability Powder Coated for finish longevity SKU: CS-FMRC-05 Fitment: 2020+ F250/350 4x4, Diesel - 5.5" of lift Fitment: 2005-19 F250/350 4x4, Diesel - 4.5" of lift Progressive Rate Spring Shot peened & Pre-set for Maximum Durability Powder Coated for finish longevity