Bilstein 22-306623 Suspension Strut Assembly - Front Left

Bilstein B4 OE Replacement Front Left Strut

The Bilstein B4 OE Replacement suspension strut assembly is built to restore original ride quality and handling on select BMW applications. This front left unit uses a twin-tube internal design with a black painted finish and OE-style mounting points for a direct replacement on supported vehicles.

For drivers searching for a Bilstein 22-306623 front left strut for BMW 330i xDrive, M340i xDrive, 430i xDrive, or M440i xDrive, this B4 OE Replacement part is engineered to meet or exceed OE standards while maintaining factory ride characteristics.

Key Features

• Bilstein B4 OE Replacement series
• Part number 22-306623
• Front left suspension strut assembly
• Twin-tube internal design
• Black painted finish
• Stem upper mount and base cup lower mount
• Boot not included
• OE-style replacement for factory ride and handling

Product Line Details

The Bilstein B4 OE Replacement line focuses on restoring original suspension behavior for vehicles that left the factory with a specific ride and damping feel. This series is aimed at drivers who want a direct OE replacement strut assembly rather than a performance-tuned upgrade, making it a practical choice for maintaining factory-like comfort and control.

Fitment

• Fits 2021-2025 BMW 430i xDrive, front left, sport suspension without electronic suspension; B4 OE Replacement.
• Fits 2025 BMW M440i xDrive, front left, sport suspension without electronic suspension; B4 OE Replacement.
• Fits 2019-2024 BMW 330i xDrive, front left, sport suspension without electronic suspension; B4 OE Replacement.
• Fits 2020-2024 BMW M340i xDrive, front left, without electronic suspension; B4 OE Replacement.
• Fits 2021-2024 BMW M440i xDrive, front left, without electronic suspension; B4 OE Replacement.

What It Helps Address

• Front-end ride harshness from a worn strut
• Excessive bouncing after bumps or dips
• Reduced steering stability and road control
• Uneven suspension response on the front left corner
• Factory ride quality loss on BMW xDrive sport suspension setups

Installation Notes and Tips

Install this strut on the front left position only and verify that the vehicle is equipped with the listed suspension configuration before ordering. This part cross-references BMW OE numbers 31 31 6 879 311 and 31 31 6 879 313 for the same application. Because the upper mount is stem-style and the lower mount is a base cup design, confirm the original mounting layout during service and inspect related suspension components at the same time.

Quality Assurance

Bilstein manufactures the B4 OE Replacement line to meet or exceed OE standards, with a focus on restoring original ride quality and handling characteristics. The part number 22-306623 is built as an OE-style replacement for supported BMW applications.