Rancho RS55227 RS5000X Rear Shock 88-00 Chevy/GMC K1500 K2500 K3500 Blazer Tahoe

Vehicle Fitment

• 1988-2000 Chevrolet K1500 (4WD; All Trims; All Cabs)
• 1988-2000 Chevrolet K2500 (4WD; All Trims; All Cabs)
• 1988-2000 Chevrolet K3500 (4WD; All Trims; All Cabs)
• 1992-1999 Chevrolet K1500 Suburban (4WD)
• 1992-1998 Chevrolet K2500 Suburban (4WD)
• 1992-1994 Chevrolet K Blazer (full-size; 4WD)
• 1995-1999 Chevrolet Tahoe (4WD)
• 1988-2000 GMC K1500 Sierra (4WD; All Trims; All Cabs)
• 1988-2000 GMC K2500 Sierra (4WD; All Trims; All Cabs)
• 1988-2000 GMC K3500 Sierra (4WD; All Trims; All Cabs)
• 1992-1999 GMC K1500 Suburban (4WD)
• 1992-1999 GMC Yukon (4WD)

Fitment Notes

• This is the rear shock absorber for the GMT400 platform (1988-2000 full-size Chevrolet and GMC trucks and SUVs). It is not the front shock - the front shock for these vehicles is a separate part number.
• This part number (RS55227) fits the GMT400 full-size C/K truck and SUV platform only. Confirm your vehicle is 4WD (K-series) before ordering - 2WD (C-series) models use different rear shock geometry and part numbers.
• The RS55227 spans multiple rear lift height applications on this platform. With a 12.24-inch travel and 29.56-inch extended length, this is a long-travel rear shock confirmed for use in 2.5-4" rear lift configurations as well as stock-height applications on the GMT400 Suburban. Confirm your vehicle's rear lift height configuration before ordering.
• Factory shock mounting hardware is reused. All necessary washers, bushings, and nuts are included. Sold individually - order two units for a complete rear pair.

Features

• Cross Tuned technology with Progressive Engagement Valving (PEV) - the RS5000X's patented eccentric disc valve shim stacks engage at lower piston velocities before the main valving opens, providing a graduated damping response that absorbs initial compression inputs progressively; on the GMT400 platform - which spans K1500 half-ton pickups through K3500 one-ton dually trucks and full-size Suburban/Tahoe/Yukon SUVs - the progressive engagement characteristic improves ride quality over rough surfaces by softening the initial shock response before transitioning to full damping force at higher-velocity inputs from deeper potholes, highway washboarding, and trail obstacles
• Tuned Compression Control Valve - a dedicated precision-shim-stacked compression valve regulates fluid transfer during the compression stroke, calibrated for the GMT400's rear leaf spring suspension rates; the valve manages fluid flow without disc flutter, providing consistent damping behavior across the wide range of payload and towing conditions that GMT400 trucks are regularly used in
• Long travel design - the RS55227's 12.24-inch stroke and 29.56-inch extended length provide the travel capacity needed on the GMT400 platform across both stock-height and lifted configurations; the rear leaf spring suspension of the GMT400 trucks generates substantial shock travel under load and off-road articulation, and the RS55227's extended length accommodates this without reaching full droop prematurely
• Nitrogen gas pressurization at 150 PSI - the gas charge suppresses aeration and foaming of the hydraulic fluid under sustained cycling, maintaining consistent damping performance during the towing, hauling, and trail-driving conditions that GMT400 trucks are frequently subjected to
• Enlarged 2.25-inch twin-tube body - the larger reserve tube diameter provides greater fluid capacity than standard-bore shocks, enabling lower operating temperatures during sustained heavy-duty use; on full-size trucks and SUVs that regularly operate at high payload weights and towing loads - conditions that cycle the rear shocks more aggressively than passenger-car use - the increased fluid volume directly reduces the risk of thermal fade
• 16mm nitro-carburized chrome piston rod - the surface hardening process increases rod hardness to resist scoring from grit that enters around the upper seal; on trucks used for work and off-road driving, extended rod surface hardness is directly correlated with seal longevity and resistance to premature oil weeping
• 35mm sintered iron piston with fluon band - the larger piston diameter improves the precision of the damping response; the fluon-banded outer surface provides low-friction guidance within the shock body, reducing stick-slip at piston initiation and improving small-bump sensitivity
• Polyurethane rebound bumper - the end stop bumper absorbs the energy of the shock reaching full extension, preventing metal-to-metal contact at the droop limit and the associated chassis impact transmitted during rapid wheel unloading
• Low-friction, self-lubricating seal - the rod seal maintains consistent low-friction operation over its service life, contributing to small-bump response quality and preventing premature oil loss
• Double-welded loops at stress areas - the eyelet mounting loops are double-welded at the highest-stress concentration points for structural reinforcement at the fatigue locations that experience the most cyclical loading under heavy-duty use
• Polyvinyl protective boot (red) - protects the piston rod and upper seal from direct debris and mud contact in the undercarriage environment

Specifications

• Part Number: RS55227
• Series: RS5000X
• Position: Rear
• Fitment: 1988-2000 Chevrolet/GMC K1500, K2500, K3500; Suburban; Blazer; Tahoe; Yukon (4WD)
• Internal Design: Twin-tube, gas pressurized
• Gas Charge: Nitrogen, 150 PSI
• Body Diameter: 2.25 in. (enlarged twin-tube)
• Piston Rod: 16mm nitro-carburized chrome
• Piston: 35mm sintered iron, fluon-banded
• Compressed Length: 17.33 in.
• Extended Length: 29.56 in.
• Shock Travel: 12.24 in.
• Upper Mount: XP5
• Lower Mount: LS92
• Operating Temperature: -40°F to 248°F
• Adjustable: No
• Quantity: 1 shock (single - order 2 for complete rear pair)
• Warranty: Limited Lifetime

Included Components

• 1x Rancho RS5000X rear shock absorber (RS55227)
• Polyvinyl protective boot (red)
• Mounting hardware (bushings, washers, nuts)

Product Description

The Rancho RS55227 is an RS5000X series rear shock absorber for the GMT400 full-size Chevrolet and GMC truck and SUV platform - covering K1500, K2500, and K3500 pickups from 1988 through 2000, along with the full-size Blazer, Suburban, Tahoe, and Yukon 4WD variants in the same generation. This is a long-travel rear shock with 12.24 inches of stroke and 29.56 inches of extended length, suitable for stock-height through lifted rear suspension applications on these platforms.

The RS5000X's Cross Tuned Progressive Engagement Valving provides a graduated damping response that benefits the GMT400's rear leaf spring suspension - softening initial impact response over rough surfaces while retaining the full damping force needed under heavy payload, towing loads, and off-road articulation. The 150 PSI nitrogen gas charge and enlarged 2.25-inch twin-tube body manage heat buildup during sustained use, maintaining consistent performance through the demanding work and trail conditions that GMT400 trucks regularly encounter. The 16mm nitro-carburized rod, 35mm fluon-banded sintered iron piston, and double-welded mounting loops provide the structural durability needed on heavy-duty truck applications.

This is the rear shock only - the front shock for the 1988-2000 K-series GMT400 is a separate part number. Confirm 4WD configuration before ordering; 2WD C-series variants require different rear shocks. Sold individually; two units required for a complete rear pair. Backed by Rancho's Limited Lifetime Warranty.