Built to Last: Low-friction, self-lubricating seal retains gas and oil for quicker rebound and smoother compression while the application-specific piston delivers heightened control of shock motion due to the expanded piston area Durable and Long-Lasting: Built to withstand the toughest of terrains and weather conditions, these Rancho products are made from high-quality materials that are built to last Improved Handling and Stability: Whether you're navigating rough terrain or taking on winding roads, the Rancho RS5000X shocks provide improved handling and stability, giving you better control of your vehicle Maintains Vehicle Control: Compression Control Valve is custom-tuned for each vehicle to regulate fluid transfer to absorb impacts without disc flutter and help maintain shock motion control Vehicle Compatibility: This fits your 1999-2005 Silverado 1500 & Sierra 1500 with 0 inch lift and 2007 Silverado 1500 Classic & Sierra 1500 Classic RWD with 0 inch lift; Without Electronic Ride Control Page (ZXE) Featuring a unique, exclusive valving system and advanced compression functionality, Rancho RS5000X shocks deliver improved overall on- and off-road handling and performance. Cross Tuned technology featuring exclusive rebound valving system and advanced compression phase improves overall handling and performance on and off road. Exclusive Progressive Engagement Valving is custom-tuned for each vehicle to help reduce initial impacts at low speeds and minimizes a rough ride. It features a 16mm nitro-carburized piston rod to resist scuffs & corrosion, double-welded loops at stress areas, 35mm sintered iron piston for enhanced structural integrity and polyvinyl protective boot. Large twin-tube body filled with all-weather fluid allows for cooler operation, increased vehicle control and ability to withstand internal temperatures of -40 to 248°F. Nitrogen gas pressurized to 150 PSI to minimize air-to-oil mixture to reduce damping performance fade and foaming. From its humble beginnings in 1955 to the present, Rancho has been dedicated to delivering suspension systems, shock absorbers and accessories that deliver rugged on- and off-road performance for Jeeps, trucks and SUVs. From its humble beginnings in 1955 to the present, Rancho has been dedicated to delivering suspension systems, shock absorbers and accessories that deliver rugged on- and off-road performance for Jeeps, trucks and SUVs.