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
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