KYB 555051 Shock Absorber - Rear

KYB Gas-a-Just Rear Shock for Frontier

The KYB Gas-a-Just 555051 is a rear monotube shock absorber built for Nissan Frontier applications that need firmer control and consistent damping. It is engineered to respond quickly during normal driving and add damping on demand when the suspension is working harder.

For 2005-2021 Nissan Frontier rear applications, this shock uses a high-pressure monotube design that separates gas and oil for fade-resistant operation. The Gas-a-Just line is focused on vehicles that tow, carry loads, or run larger tires and wheels, and this part number 555051 is tuned for Frontier-specific fitment.

Key Features

• Up to 25% more damping performance than original equipment shocks
• Monotube construction with separate gas and oil chambers for consistent response
• High-pressure nitrogen gas helps maintain control during demanding driving
• Triple chrome plated piston rod helps reduce seal wear and fluid leakage
• Improves steering response through higher gas pressure and quicker reaction
• Designed specifically for Nissan Frontier rear suspension applications
• Dust cover included

Detailed Description

KYB Gas-a-Just shocks are designed around a monotube layout with an air-free hydraulic working area and a separate high-pressure gas chamber. That design supports immediate damping response and helps reduce fade caused by aeration. On the Nissan Frontier, part number 555051 provides rear suspension control for drivers who want more stability than a standard twin-tube shock can deliver.

The Gas-a-Just product line is intended for trucks that work harder than average, including Nissan Frontier models used for towing, hauling, or fitted with heavier tires and wheels. This rear shock absorber measures 13.58 inches compressed, 20.9 inches extended, and 7.32 inches of stroke length. Mounting details include lower mount type E2(14X42) and upper mount type E1.

This part cross-references Monroe Shocks & Struts (e.g., 37273) for the same application.

What It Helps Address

• Excessive rear bounce over bumps and uneven pavement
• Reduced control when towing or carrying added weight
• Delayed suspension response from worn OE shocks
• Fade from heat and aeration during repeated suspension movement
• Loose rear-end feel on Nissan Frontier trucks with larger tires and wheels

Installation Notes and Tips

Fits 2005-2021 Nissan Frontier, rear. Fits 2006 Nissan Frontier, rear, from 09/2005 with monotube performance upgrade notes. Verify mount style, compressed length, and extended length before installation. Replace shocks in matched axle pairs when servicing the rear suspension, and inspect bushings, mounts, and surrounding hardware for wear before final assembly.

Quality Assurance

KYB is a major OE suspension supplier, and the Gas-a-Just line is built to meet the demands of truck and performance-oriented applications. Part number 555051 is engineered for consistent damping, reduced fade, and dependable rear suspension control on Nissan Frontier models.