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KYB KG4521 Axle Shaft Damper


Brand:	KYB
Part Number:	KG4521
UPC:	781552045212
Weight:	2.69 lbs
Condition:	New

On Sale:

$39.17

Availability:

2 in Stock

Warehouse:

US-1

Quantity:

Product Information

Description:

Get the KYB KG4521 Axle Shaft Damper for your vehicle. Buy now and secure your purchase online!

The KYB Gas-a-just monotube shock absorber has additional performance advantages over the traditional twin-tube design: It can instantly, automatically adjust to your performance needs and never experiences fade due to aeration. The KYB Gas-a-just has two separate working chambers: An air-free hydraulic piston and valve area for responsiveness and control, and a second high-pressure nitrogen gas area with a floating piston that provides a comfortable ride during normal driving and adds instant performance on demand.

Features and Benefits:

Adds up to 25% more damping performance over original equipment shocks
Components and valving designed specifically for your vehicle
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.
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
Gas-a-Just monotubes include additional damping over OE design for vehicles that work, tow, and have larger, heavier tires & wheels
High pressure monotube design separates the gas and oil for fade free operation and instant response
The higher gas pressure of the KYB Gas-a-Just responds quickly to improve steering response

Specifications:

B-stop:

Compressed Length:

10.55

Dust Cover Included:

Extended Length:

16.26

Internal Rebound Spring:

Lower Mount Type:

E2(12x32)

R-stop:

Stroke Length:

5.71

Upper Mount Type:

E2(12x32)

Country of Origin:

Select a vehicle to narrow KYB KG4521 Axle Shaft Damper fitment info!

Last Updated: 04/17/2024

Years

Vehicle

Per Vehicle

Position

Fit Notes

Fitment Notes

Ford Mustang

4.6L V8 Gas SOHC

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

4.6L V8 Gas SOHC Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Mustang

3.8L V6 Gas OHV

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

3.8L V6 Gas OHV Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

2001

Ford Mustang

4.6L V8 Gas DOHC

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

4.6L V8 Gas DOHC Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

2000

Ford Mustang

5.4L V8 Gas DOHC

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

5.4L V8 Gas DOHC Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Mustang

4.6L V8 Gas DOHC

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

4.6L V8 Gas DOHC Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

1995

Ford Mustang

5.8L V8 Gas OHV

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

5.8L V8 Gas OHV Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Mustang

5.0L V8 Gas OHV

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

5.0L V8 Gas OHV Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Mustang

2.3L L4 Gas SOHC

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

2.3L L4 Gas SOHC Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Mustang

2.3L L4 Gas SOHC Turbo,
3.8L V6 Gas OHV

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

2.3L L4 Gas SOHC Turbo,
3.8L V6 Gas OHV Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Thunderbird

2.3L L4 Gas SOHC Turbo,
3.8L V6 Gas OHV,
5.0L V8 Gas OHV

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Thunderbird

2.3L L4 Gas SOHC Turbo,
3.8L V6 Gas OHV,
5.0L V8 Gas OHV Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Mercury Capri

2.3L L4 Gas SOHC,
3.8L V6 Gas OHV,
5.0L V8 Gas OHV

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Mercury Capri

2.3L L4 Gas SOHC,
3.8L V6 Gas OHV,
5.0L V8 Gas OHV Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

1984

Mercury Capri

2.3L L4 Gas SOHC Turbo

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Mercury Capri

2.3L L4 Gas SOHC Turbo Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Mercury Cougar

3.8L V6 Gas OHV,
5.0L V8 Gas OHV

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Mercury Cougar

3.8L V6 Gas OHV,
5.0L V8 Gas OHV Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Mercury Cougar

2.3L L4 Gas SOHC Turbo

2 Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Mercury Cougar

2.3L L4 Gas SOHC Turbo Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

KYB KG4521 Axle Shaft Damper

$39.17

Product Information

Description:

Features and Benefits:

Specifications:

Select a vehicle to narrow KYB KG4521 Axle Shaft Damper fitment info!

Ford Mustang 4.6L V8 Gas SOHC

2

Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

4.6L V8 Gas SOHC Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm). 2 Per Vehicle

Ford Mustang 3.8L V6 Gas OHV

2

Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

3.8L V6 Gas OHV Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm). 2 Per Vehicle

Ford Mustang 4.6L V8 Gas DOHC

2

Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

4.6L V8 Gas DOHC Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm). 2 Per Vehicle

Ford Mustang 5.4L V8 Gas DOHC

2

Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

5.4L V8 Gas DOHC Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm). 2 Per Vehicle

Ford Mustang 4.6L V8 Gas DOHC

2

Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

4.6L V8 Gas DOHC Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm). 2 Per Vehicle

Ford Mustang 5.8L V8 Gas OHV

2

Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

5.8L V8 Gas OHV Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm). 2 Per Vehicle

Ford Mustang 5.0L V8 Gas OHV

2

Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

5.0L V8 Gas OHV Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm). 2 Per Vehicle

Ford Mustang 2.3L L4 Gas SOHC

2

Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

2.3L L4 Gas SOHC Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm). 2 Per Vehicle

Ford Mustang 2.3L L4 Gas SOHC Turbo,3.8L V6 Gas OHV

2

Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

Ford Mustang

2.3L L4 Gas SOHC Turbo,3.8L V6 Gas OHV Gas-a-justAxle Damper (Rear Quad Shock) Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm). 2 Per Vehicle

Ford Mustang

4.6L V8 Gas SOHC

Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

4.6L V8 Gas SOHC Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Mustang

3.8L V6 Gas OHV

Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

3.8L V6 Gas OHV Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Mustang

4.6L V8 Gas DOHC

Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

4.6L V8 Gas DOHC Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Mustang

5.4L V8 Gas DOHC

Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

5.4L V8 Gas DOHC Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Mustang

4.6L V8 Gas DOHC

Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

4.6L V8 Gas DOHC Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Mustang

5.8L V8 Gas OHV

Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

5.8L V8 Gas OHV Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Mustang

5.0L V8 Gas OHV

Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

5.0L V8 Gas OHV Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Mustang

2.3L L4 Gas SOHC

Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2.3L L4 Gas SOHC Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle

Ford Mustang

2.3L L4 Gas SOHC Turbo,
3.8L V6 Gas OHV

Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2.3L L4 Gas SOHC Turbo,
3.8L V6 Gas OHV Gas-a-just
Axle Damper (Rear Quad Shock)
Install KG4521 with the dustcover to the rear of the vehicle, the spacers (in box) to the inboard side of the shock, and the axle mounting bracket spread slightly (1-2mm).

2 Per Vehicle