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KYB Suspension 5540004 Gas-a-Just High Pressure Monotube Gas Shock Absorber

(2014-2015 Lexus IS250 Base/F Sport/GS; 2016-2021 Lexus IS300; 2014-2020 Lexus IS350 Base/GS; 2016-2017 Lexus IS200t)

Part of: KYB Suspension Gas-a-Just Monotube High Pressure Gas Shock Absorber

Other options in this family: KYB Suspension KG54317 KYB Suspension KG5462 KYB Suspension KG4752 KYB Suspension 554348 KYB Suspension KG5440

Manufacturer

Picture for manufacturer KYB Suspension

Part Number

5540004
6 reviews
Sale Price

$75.70

In Stock (10+)

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Usually delivered within 2 days

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Fitment guaranteed

Fitment guaranteed

Product Details

The KYB Gas-a-Just 5540004 is a high-performance monotube gas shock absorber engineered to deliver superior handling and responsiveness compared to traditional twin-tube designs. This advanced shock absorber automatically adjusts to changing road conditions and driving demands, providing both comfort during normal driving and enhanced performance when you need it most.

Key Features:

  • Monotube design with dual separate working chambers for optimal performance
  • Air-free hydraulic piston and valve area ensures instant responsiveness and precise control
  • High-pressure nitrogen gas chamber with floating piston provides consistent damping force
  • Fade-free performance eliminates aeration issues common in twin-tube designs
  • Automatically adjusts to performance needs without driver input
  • Available as direct OE monotube replacement or performance upgrade for OE twin-tube shocks
  • Delivers comfortable ride quality during normal driving with on-demand performance capability

The Gas-a-Just monotube design separates the hydraulic fluid from the nitrogen gas charge using a free-floating piston, preventing fluid aeration and maintaining consistent damping characteristics under all driving conditions. This engineering approach provides immediate response to suspension inputs while maintaining ride comfort for daily driving applications.

Products specifications

Fits

2014-2015 Lexus IS250 Base/F Sport/GS; 2016-2021 Lexus IS300; 2014-2020 Lexus IS350 Base/GS; 2016-2017 Lexus IS200t

Compressed Length

18.5

Extended Length

24.05

Stroke Length

5.55

Lower Mount Type

E2(14.2X70)

Feature and Benefit 7

ELECTRONIC SAFETY SYSTEMS DEPEND ON THE SUSPENSION, BRAKES AND TIRES OPERATING AS THE VEHICLE MANUFACTURER INTENDED. THE KYB GAS-A-JUST HELPS KEEP ELECTRONIC SAFETY SYSTEMS PERFORMING AS DESIGNED.

Feature and Benefit 5

FLUID LEAKING CAN BE A CAUSE OF SHOCK FAILURE, THE KYB GAS-A-JUST HAS AN ULTRA-SMOOTH TRIPLE CHROME PLATED CHROME PISTON ROD TO REDUCE SEAL WEAR

Feature and Benefit 3

GAS-A-JUST MONOTUBES ARE DESIGNED FOR VEHICLES THAT WORK, TOW, AND HAVE LARGER, HEAVIER TIRES & WHEELS

Feature and Benefit 4

HIGH PRESSURE MONOTUBE DESIGN SEPARATES THE GAS AND OIL FOR FADE FREE OPERATION AND INSTANT RESPONSE

Internal Rebound Spring

INTERNAL REBOUND SPRING

Dust Cover Included

N

B-stop

N

Upper Mount Type

S1(12MM)

FEATURE AND BENEFIT 1

THE CORRECT, MONOTUBE-DESIGNED OEM REPLACEMENT

Feature and Benefit 6

THE HIGHER GAS PRESSURE OF THE KYB GAS-A-JUST RESPONDS QUICKLY TO IMPROVE STEERING RESPONSE

Feature and Benefit 2

THE KYB GAS-A-JUST HELPS RESTORE THE DESIGNED CONTROL AND HANDLING OF YOUR LEXUS IS250 & IS350 (RWD)

R-stop

Y

Internal Rebound Spring

Y

ordering was easy and simple. found my part fast and easy.

I located a Coupon Chief verified 'free shipping with most orders' coupon for your firm that was not accepted when checking out.

fast and easy

great price -

excellent... best deal I could find.

Great pricing

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