Rancho RS55387 Shock Absorber - Rear

Rancho RS5000X Rear Shock for Trailblazer and Envoy

The Rancho RS5000X rear shock absorber is built for drivers who want more controlled handling on pavement and more consistent damping on rough roads. Part number RS55387 uses Rancho’s RS5000X valving approach and advanced compression control to improve ride response on the rear suspension.

Key Features

• Rancho RS5000X shock absorber for rear suspension applications
• Exclusive valving system for more controlled on-road and off-road performance
• Advanced compression functionality for improved damping response
• Compressed length: 14.56 in.; extended length: 23.21 in.
• Travel length: 8.66 in. with a 2.251 in. reserve tube diameter
• Dust shield included for added protection
• Extended bumper stop included; compressed bumper stop not included
• Upper mount: LS40 loop bushing and sleeve mount
• Lower mount: loop bushing and sleeve mount with 1/2 in. sleeve ID

Product Details

Rancho RS55387 is a rear suspension shock absorber engineered for vehicles that need stable rear-end control over changing road surfaces. The RS5000X line focuses on refined valving and compression behavior, helping the shock respond more consistently during everyday driving and when the suspension is working harder. This part cross-references KYB 343395 for the same application. Compatible fitment includes 2002-2009 Chevrolet Trailblazer rear, 2002-2009 GMC Envoy rear, 2003-2008 Isuzu Ascender rear, 2003-2006 Chevrolet SSR rear, 2002-2006 Chevrolet Trailblazer EXT rear, 2002-2006 GMC Envoy XL rear, 2004-2005 GMC Envoy XUV rear, and 2002-2004 Oldsmobile Bravada rear.

What It Helps Address

• Excessive rear suspension bounce over uneven pavement
• Reduced control during braking, cornering, or lane changes
• Rear-end instability on rough roads or light off-road surfaces
• Worn shock performance that can affect ride quality
• Inconsistent damping response from aging suspension components

Installation Notes and Tips

Verify upper and lower mount styles before installation: LS40 upper loop bushing and sleeve mount, and lower loop bushing and sleeve mount with 1/2 in. sleeve ID. Confirm rear application and suspension height; listed fitment is for 0 inch raised height where noted. Compare compressed and extended lengths to the original shock to ensure proper suspension travel and clearance.

Quality Assurance

Rancho RS5000X shocks are built around a valving system and compression-focused design intended to deliver consistent rear suspension control. RS55387 is specified for direct rear fitment on the listed Chevrolet, GMC, Isuzu, and Oldsmobile applications.