Rancho RS5000 Hydro Shocks & Stabilizer Kit 08-16 Ford F-350 SD 4WD Set of 4 Shocks & One Steering Stabilizer - Fits 4WD Vehicles Shock boots included with all shocks. Hydraulic damping and velocity-sensitive valving generate a damping force proportional to the velocity of compression or extension of the shock. Slow compression provides low resistance fast compression provides greater resistance. All necessary washers, bushings, and nuts included. Factory shock mounting bolts are reused for installation. Rancho's limited lifetime warranty protects against defects and premature failure.