Rancho RS5000X Rear Shock Absorber for 1999-2004 Ford F-250/F-350 Super Duty - RS55273

Fits 1999-2004 Ford F-250 and F-350 Super Duty pickup trucks across all submodels, including Lariat, XL, XLT, King Ranch, and Harley-Davidson editions.

The Rancho RS5000X RS55273 rear shock absorber is engineered to deliver improved handling and control for heavy-duty applications. Built with a large 2.25-inch twin-tube body, this shock utilizes an application-specific piston and Rancho’s exclusive Progressive Engagement Valving (PEV) system. This custom-tuned valving helps reduce harshness during initial low-speed impacts while maintaining firm control on rough terrain and off-road conditions.

Designed for durability in extreme environments, the RS55273 is filled with all-weather fluid capable of resisting internal temperatures from -40 to 248°F. The system is nitrogen-pressurized to 150 PSI, which minimizes air-to-oil mixture to prevent foaming and damping fade. Each shock features a 16mm nitro-carburized piston rod for enhanced corrosion resistance and double-welded loops at high-stress areas for long-term structural integrity.

• Precision Control: 35mm sintered iron piston and fluon-banded piston design for smooth, responsive fluid transfer.
• Heavy-Duty Build: 16mm nitro-carburized rod resists scuffs and corrosion better than standard chrome.
• Temperature Stable: Twin-tube body and all-weather fluid ensure consistent performance in extreme heat or cold.
• Internal Protection: Polyurethane rebound bumper and rubber bushings help absorb ride harshness.
• Complete Kit: Includes a durable polyvinyl protective boot to keep debris away from the seal and rod.
• Manufacturer Part Number: RS55273