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Bilstein 2021+ Mercedes-Benz S500/S580 B4 OE Replacement (Air) Monotube Strut - Rear Left

Bilstein
BIL44-400187
651860953861
Shocks and Struts
13 Units In Stock - Ships Next Business Day
$ 1,386.00 $ 1,299.00
FREE Ground Shipping!
$ 1,299.00

SKU: 44-400187   |   UPC: 840123520029

Bilstein B4 OE Replacement (Air) Monotube Strut - Rear Left 2021+ Mercedes-Benz S500/S580/S580e

The Bilstein 44-400187 B4 OE Replacement (Air) Monotube Strut is the best direct replacement for the rear left air suspension strut on 2021+ Mercedes-Benz S500, S580, and S580e models. As an OE supplier for air suspension systems, Bilstein B4 dampers meet and exceed the original equipment standards, restoring 100% factory functionality and ride quality. Manufactured with 100% new parts for maximum reliability and safety, these monotube struts connect directly into the original connectors for modification-free installation, ensuring the original feel of the vehicle is fully restored.

Key Features

  • Restores Original Functionality 100%: Exact match to factory performance and ride quality
  • Manufactured with 100% New Parts: Maximum reliability and safety
  • 100% OE Quality and Comfort: Meets and exceeds original equipment standards
  • Direct Fit Installation: Connects directly into original connectors with no modifications required
  • Monotube Design: Superior damping control and heat dissipation
  • Bilstein Quality: German engineered and OE supplier for Mercedes-Benz air suspension

Specifications

Specification Detail
Part Number 44-400187
Position Rear Left
Type B4 OE Replacement (Air) Monotube Strut
Compatibility 2021+ Mercedes-Benz S500, S580, S580e with Air Suspension (without E-Active Suspension, without 4-Wheel Steering)
Installation Direct Replacement
Country of Origin Germany
Warranty Limited (Bilstein)
Shipping Weight Approx. 15 to 20 lbs

What's Included

  • One Rear Left B4 OE Replacement (Air) Monotube Strut

Product Notes

  • Specifically for vehicles equipped with air suspension
  • Restores factory ride quality and handling
  • Direct plug-and-play replacement for original air strut

Installation Notes

  • Estimated time: 2 to 4 hours, moderate to advanced difficulty, professional installation highly recommended
  • Direct replacement using factory connectors and mounting points
  • Professional alignment and system calibration recommended after installation

This Part Fits

Year Make Model Notes
2021 to 2025 Mercedes-Benz S500 4Matic L6.2999cc - Without E-Active Suspension, Without 4-Wheel Steering, With Air Suspension
2021 to 2025 Mercedes-Benz S580 4Matic V8.3982cc - Without E-Active Suspension, Without 4-Wheel Steering, With Air Suspension
2023 to 2025 Mercedes-Benz S580e 4Matic L6.2999cc - Without E-Active Suspension, Without 4-Wheel Steering, With Air Suspension

Why Choose Bilstein B4 OE Replacement Air Strut?

  • Exact OE replacement restores 100% factory functionality and ride quality
  • 100% new parts for maximum reliability and safety
  • Direct plug-and-play installation with original connectors

Frequently Asked Questions

  • Q: Will this strut fit my 2022 Mercedes-Benz S580 with air suspension?
    A: Yes, Bilstein 44-400187 fits 2021+ Mercedes-Benz S-Class models with air suspension (without E-Active Suspension and without 4-Wheel Steering).
  • Q: Is this the left or right side?
    A: This is the Rear Left strut.
  • Q: Does it include the air spring?
    A: Yes, this is a complete OE replacement air strut module.
  • Q: What is the warranty?
    A: Covered by Bilstein limited warranty built for performance.

Shipping & Handling

  • Method: UPS / FedEx Ground
  • Availability: In stock ships same or next business day
  • Packaging: Secure protective packaging
  • Weight: Approx. 15 to 20 lbs

Request For Information

Have questions about Bilstein 2021+ Mercedes-Benz S500/S580 B4 OE Replacement (Air) Monotube Strut - Rear Left? Fill out the form below and we'll get back to you by the next business day.
Bilstein

Bilstein

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