KYB 5540055 Gas-a-Just Monotube Gas Shock Absorber

The KYB 5540055 Gas-A-Just is a high-pressure monotube gas shock absorber engineered to deliver superior handling, stability, and fade-free performance. Designed as either a direct OE monotube replacement or a performance upgrade over factory twin-tube shocks, the Gas-A-Just raises the bar for ride control and road-holding confidence.

Unlike conventional twin-tube designs where gas and oil can mix and foam under aggressive driving conditions, the Gas-A-Just monotube design keeps gas and oil completely separated, eliminating aeration-related fade and maintaining consistent damping force in all conditions. The result is an immediate, responsive feel that automatically adjusts to changing road conditions without sacrificing ride comfort during everyday driving.

Key Features:

• High-pressure monotube design operating at 280 psi keeps tires firmly planted and delivers up to 25% more damping than OE twin-tube shocks
• Two separate working chambers — an air-free hydraulic piston and valve area for responsiveness, plus a high-pressure nitrogen gas chamber with a floating piston for on-demand performance
• Triple chrome-plated piston rod provides an ultra-smooth surface to minimize seal wear and extend service life
• Multi-lip synthetic oil seal with integrated wiper retains fluid and blocks contaminants from entering the oil
• Fade-free operation — monotube construction eliminates hydraulic fluid foaming that causes performance loss in twin-tube shocks
• Improved steering response — higher gas pressure allows the shock to react instantly for better vehicle control during lane changes and braking
• Reduced stopping distance — helps hold the vehicle level under braking to improve brake effectiveness and longevity
• Ideal for trucks, 4x4s, and SUVs with higher roll centers, as well as high-performance cars requiring precise suspension control
• Compatible with larger aftermarket wheels and tires — better equipped than standard OE shocks to manage the added unsprung weight
• KYB Lifetime Warranty — backed by KYB's manufacturer limited lifetime warranty against defects for the original purchaser

The KYB Gas-A-Just 5540055 includes all necessary installation hardware (washers, bushings, and nuts). Factory shock mounting bolts are reused. Shock boots are sold separately. Sold individually.