KYB KG5508 Shock Absorber - Rear

KYB Gas-a-Just Rear Shock KG5508

The KYB Gas-a-Just KG5508 is a monotube suspension shock absorber built as an OE-style replacement for classic GM rear applications. It uses separate hydraulic and high-pressure gas chambers to improve response, control fade, and maintain a consistent ride during normal driving and load changes.

Gas-a-Just Product Line

KYB Gas-a-Just shocks are designed for vehicles that work harder than a standard commuter car, including classic GM cars with larger tires and wheels or added load demands. The monotube design provides additional damping over OE design, while the high gas pressure helps the shock react quickly to steering and suspension movement.

Key Features

• Adds up to 25% more damping performance over original equipment shocks
• High-pressure monotube design separates gas and oil for fade-free operation and instant response
• Triple chrome plated piston rod helps reduce seal wear and fluid leakage
• Designed specifically for classic GM cars
• Improves steering response through higher gas pressure
• Supports electronic safety systems by helping the suspension operate as engineered
• Dust cover included

Detailed Description

Part number KG5508 is a rear suspension shock absorber with a compressed length of 14.53 inches, an extended length of 23.78 inches, and a 9.25-inch stroke. It uses lower mount type E1 and upper mount type E3 (61.6 x 87 x 20). The Gas-a-Just design keeps the gas and oil separated with a floating piston, which helps maintain consistent damping and quick reaction under changing road conditions. This makes the KYB KG5508 a practical choice for restoring rear suspension control on classic Cadillac, Buick, and Oldsmobile applications.

This part cross-references Monroe Shocks & Struts 5820 for the same application.

What It Helps Address

• Excessive rear bounce after bumps
• Reduced damping control from worn OE shocks
• Fluid leakage caused by seal wear
• Slow steering or suspension response
• Ride instability on vehicles with heavier tires and wheels

Installation Notes

Fits 1971-1976 Cadillac DeVille, rear, excluding electronic suspension and commercial chassis. Fits 1965-1970 Buick LeSabre, rear. Fits 1965-1968 Oldsmobile 98, rear. Fits 1965-1968 Oldsmobile Delta 88, rear. For Buick LeSabre, Oldsmobile 98, and Oldsmobile Delta 88 applications, replace the suspension strut and coil spring assembly according to the manufacturer’s instructions. Verify mount style and dimensions before installation.

Quality Assurance

KYB designs Gas-a-Just shocks as OE monotube replacements to restore original suspension capability. The KG5508 uses a high-pressure monotube layout and a chrome piston rod to support consistent operation and reduced seal wear in demanding rear suspension service.