KYB KG4550 Shock Absorber - Front or Rear

KYB Gas-a-Just Front Shock Absorber

The KYB Gas-a-Just KG4550 is a front suspension shock absorber built for classic Chevrolet and Pontiac applications that need firmer control than a standard twin-tube design. It uses a monotube layout with separate gas and oil chambers for quick response, consistent damping, and reduced fade during demanding driving.

Key Features

• Monotube shock design with separate hydraulic and high-pressure nitrogen chambers
• Up to 25% more damping performance than original equipment shocks
• High-pressure construction helps maintain fade-free operation
• Triple chrome plated piston rod helps reduce seal wear and fluid leakage
• Improved steering response from higher gas pressure
• Valving and components tuned for classic car applications
• Designed for vehicles that work, tow, or run larger, heavier tires and wheels

Product Details

Gas-a-Just is KYB’s performance-oriented shock line for drivers who want more immediate control from the suspension without changing the vehicle’s basic ride height or geometry. The KG4550 uses a monotube architecture that separates the gas and oil, which helps the shock react quickly and resist performance loss as conditions change. For Chevrolet Corvette, Bel Air, Impala, and Pontiac Bonneville or Catalina front suspension applications, this design supports more precise body control and steadier handling.

This part cross-references Monroe Shocks & Struts 5906 for the same application.

What It Helps Address

• Excessive front-end bounce over uneven pavement
• Reduced steering response during lane changes and cornering
• Shock fade from heat and aeration in demanding use
• Fluid leakage caused by seal wear
• Loss of control feel on classic cars with heavier wheels or tires

Installation Notes and Fitment

Fits 1963-1982 Chevrolet Corvette, front. Fits 1958-1964 Chevrolet Bel Air, front, excluding air suspension. Fits 1959-1964 Chevrolet Impala, front, excluding air suspension. Fits 1961-1962 Pontiac Bonneville, front. Fits 1958-1962 Pontiac Catalina, front. Fits 1958-1960 Pontiac Bonneville, front, excluding air suspension. Fits 1955-1957 Chevrolet Bel Air, front.

Verify compressed length 9.25 in., extended length 13.54 in., and stroke length 4.29 in. before installation. Lower mount type is E3 (51.6 x 87 x 20) and upper mount type is S1. Dust cover is not included. R-stop is included. Professional installation and a final suspension inspection are recommended after replacement.

Quality Assurance

KYB designs Gas-a-Just shocks with a monotube layout and triple chrome plated piston rod to support consistent damping and reduced seal wear. The KG4550 is engineered for classic vehicle front suspension service where responsive control and stable operation matter.