Bilstein B4 DampTronic Rear Shock Absorber | BMW 1/2/3/4 Series F20 F21 F22 F23 F30 F31 F34 F32 F33 F36 EDC xDrive | OE Replacement Damper | PN 20-238933 (Fits M135i M140i M235i M240i 335i 340i 435i 440i)

Bilstein B4 DampTronic Rear Damper for BMW F-Series with EDC | Part Number 20-238933

Refresh the handling of your BMW with a direct-fit adaptive rear shock that keeps your factory electronics happy. The Bilstein B4 DampTronic rear unit delivers OE-level ride quality, crisp control and seamless compatibility with BMW Electronic Damper Control and Adaptive M Suspension systems. Ideal for sorting out tired, leaking or knocking rear shocks on F-Series 1, 2, 3 and 4 models, including xDrive all-wheel drive variants and performance trims such as M135i, M140i, M235i, M240i, 335i, 340i, 435i and 440i.

We fit these on customer cars and our own builds. Feedback is consistently positive for comfort, steering precision and stability over British roads. If you want a stock-feel replacement that just works with your EDC, this is the one.

Why it is the right choice

• Adaptive suspension ready. Plug-in connector for EDC. No warning lights. No compromise to drive modes.
• Gas-pressure technology for consistent damping, grip and confidence at speed.
• OE-spec build for factory ride height and refinement. Perfect daily road manners with strong high-speed control.
• Restores stability under braking and over bumps. Reduces bounce and improves tyre contact.
• Proven durability and quiet operation from a trusted manufacturer.

What is included

• 1 x Bilstein B4 DampTronic adaptive rear shock for the rear axle
• Part number: 20-238933

Vehicle fitment

Suits BMW F-chassis with factory electronic damping:

• 1 Series F20 F21 including M135i and M140i, rear wheel drive and xDrive
• 2 Series F22 F23 including M235i and M240i, rear wheel drive and xDrive
• 3 Series F30 F31 F34 including 335i and 340i, rear wheel drive and xDrive
• 4 Series F32 F33 F36 including 435i and 440i, rear wheel drive and xDrive

For cars equipped with BMW Electronic Damper Control or Adaptive M Suspension. If your vehicle is passive non-EDC, choose the non-DampTronic version instead.

Results you will feel

• Smoother ride with sharper response on B-roads and motorways
• Improved body control in Comfort, Sport and Sport Plus modes
• Direct replacement that maintains factory calibration and safety systems

Professional installation

Fitting available at MJ Modifications in Warwickshire. For a fitting quote or help confirming EDC compatibility, email info@mjmodifications.co.uk.

Pair for a complete refresh

For best results, replace suspension in axle pairs and consider matching front DampTronic struts to balance the chassis.

Warranty

2 year Bilstein warranty.

Brand

Bilstein.

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