Bilstein B4 OE Replacement (Air) Monotube Strut - Front Left for 2021+ Mercedes-Benz S500/S580/S580e/Maybach S680
The Bilstein 44-400156 B4 OE Replacement (Air) Monotube Strut is a direct, plug-and-play replacement for the front left air suspension strut on 2021+ Mercedes-Benz S-Class and Maybach models equipped with standard air suspension (without E-Active Suspension). As an OE supplier, Bilstein manufactures this strut to meet or exceed factory standards using 100% new parts for maximum reliability and safety. It connects directly to the vehicle’s original air lines and electrical connectors, restoring 100% original ride quality, self-leveling function, and comfort without any modifications. The monotube design with integrated air bladder delivers precise damping and long-term durability in a black painted finish.
Key Features
- Restores Original Functionality 100%
- Manufactured with 100% New Parts for Maximum Reliability and Safety
- 100% OE Quality and Comfort
- Direct Plug-and-Play Installation – No Modifications Required
- Monotube Internal Design with Integrated Air Bladder
- Self-Leveling and Air Adjustable
- Active Suspension Compatible
- Black Paint Finish for Corrosion Resistance
Specifications
| Specification | Detail |
|---|---|
| Part Number | 44-400156 |
| Position | Front Left |
| Series | B4 OE Replacement (Air) |
| Part Type | Air Spring Module |
| Internal Design | Monotube |
| Finish | Black Paint |
| Adjustable Compression | No |
| Adjustable Rebound | No |
| Adjustable Ride Height | No |
| Air Adjustable | Yes |
| Self-Leveling | Yes |
| Active or Passive Suspension | Active |
| Bladder(s) Included | Yes |
| Bladder Heavy Duty Crimping Rings Included | No |
| Strut Mount Insulator(s) Included | No |
| Bladder Sleeve(s) Included | No |
| Includes Bump Stop | No |
| Mounting Hardware Included | No |
| Grade Type | Premium |
| Country of Origin | Germany |
| Prop 65 Warning | Yes – Cancer & Reproductive Harm |
| Warranty | 2 Years (Bilstein) |
| Shipping Weight | Approx. 18 to 22 lbs |
Whats Included
- One Front Left B4 OE Replacement (Air) Monotube Strut with Integrated Bladder
Product Notes
- Designed exclusively for vehicles with standard air suspension (WITHOUT E-Active Suspension)
- Direct connection to factory air lines and connectors
- Restores factory ride height, comfort, and handling
- Ideal for replacing worn or leaking factory air struts
Installation Notes
- Estimated time: 1.5 to 3 hours (professional installation recommended)
- Utilizes factory mounting points and connectors – no modifications needed
- Depressurize air suspension system before removal per service manual
- Professional alignment recommended after installation
This Part Fits
| Year | Make | Model | Engine | Notes |
|---|---|---|---|---|
| 2022-2025 | Mercedes-Benz | Maybach S680 4Matic | V12 6.0L | Without E-Active Suspension / With Air Suspension |
| 2021-2025 | Mercedes-Benz | S500 4Matic | L6 3.0L | Without E-Active Suspension / With Air Suspension |
| 2021-2025 | Mercedes-Benz | S580 4Matic | V8 4.0L | Without E-Active Suspension / With Air Suspension |
| 2023-2025 | Mercedes-Benz | S580e 4Matic | L6 3.0L Plug-In Hybrid | Without E-Active Suspension / With Air Suspension |
Why Choose Bilstein B4 OE Replacement (Air) Strut?
- Exact OE supplier quality and direct-fit reliability
- 100% new parts no core charges or remanufactured components
- Restores factory ride comfort and safety with zero modifications
- Backed by Bilstein’s reputation for premium European vehicle suspension
Frequently Asked Questions
-
Q: Will this fit my Mercedes-Benz S-Class?
A: Yes, if your vehicle has factory air suspension and does NOT have E-Active Suspension. Verify your model year and options before ordering. -
Q: Does this include the air bladder?
A: Yes, the integrated air bladder is included and ready for direct connection. -
Q: What is the warranty?
A: Covered by Bilstein’s 2-year warranty.
Shipping and Handling
- Method: UPS / FedEx Ground
- Availability: In stock ships same or next business day
- Packaging: Secure protective packaging
- Weight: Approx. 18 to 22 lbs
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