Mercedes Air Suspension Struts Explained

Air suspension systems have become increasingly popular in modern vehicles, offering a superior ride quality and enhanced handling characteristics. Mercedes-Benz, a brand synonymous with luxury and innovation, has long been at the forefront of integrating this advanced technology into its lineup. If you're a Mercedes-Benz owner, or considering purchasing one, you might be curious about which models are equipped with these sophisticated air suspension struts. This article will delve into the specifics, particularly focusing on models that have utilised this technology, and provide insights into their operation and benefits.

Understanding Air Suspension

Before we dive into specific models, it's crucial to understand what air suspension is and how it differs from conventional spring and shock absorber setups. Instead of traditional coil springs, air suspension systems use a network of air springs, which are essentially rubber bellows filled with pressurised air. These air springs are connected to a compressor, which inflates or deflates them as needed. This allows the vehicle's ride height and stiffness to be adjusted, providing a more comfortable and adaptable driving experience. The system typically includes sensors that monitor ride height and adjust air pressure accordingly, ensuring a consistent and level ride, regardless of load or road conditions.

Key Components of an Air Suspension System

A typical Mercedes-Benz air suspension system comprises several key components:

• Air Springs: These are the core of the system, replacing traditional coil springs. They are usually made of durable rubber and are designed to hold pressurised air.
• Air Compressor: This is the 'heart' of the system, responsible for generating the pressurised air needed to inflate the air springs.
• Air Reservoir: A tank that stores compressed air, allowing for rapid inflation of the air springs when needed.
• Height Sensors: These sensors monitor the vehicle's ride height and send signals to the control unit.
• Control Unit (ECU): This electronic brain processes information from the height sensors and other inputs to regulate the compressor and air springs, adjusting the ride height and stiffness.
• Shock Absorbers: While air springs provide the spring function, shock absorbers are still present to dampen oscillations and control the movement of the suspension. In many modern systems, the air spring and shock absorber are integrated into a single unit, often referred to as an air strut.

Mercedes-Benz Models Featuring Air Suspension Struts

Mercedes-Benz has offered air suspension, often in the form of integrated air struts, across various models, particularly in its higher-end and performance-oriented vehicles. One prominent example is the:

Mercedes-Benz CLS-Class (W219)

The first generation Mercedes-Benz CLS-Class, specifically the W219 chassis, offered air suspension as a significant feature, particularly on the performance-oriented AMG models. Models such as the 2004-2011 Mercedes-Benz CLS-Class (W219 CLS55 & CLS63 AMG) were equipped with air suspension struts. These systems provided the driver with the ability to adjust the vehicle's ride height and damping characteristics, contributing to both comfort and sporty handling. For these models, components like the Arnott AS-2787 Front Right Air Suspension Strut are designed as direct replacements for the original equipment, featuring a custom-valved shock absorber and a multi-ply ContiTech air spring bladder for enhanced durability and performance. The pre-assembled nature of these struts simplifies installation, making maintenance more accessible.

Mercedes-Benz E-Class (W211)

Similarly, the 2002-2009 Mercedes-Benz E-Class (W211), especially the AMG variants like the E55 & E63 AMG, also featured advanced air suspension systems. The W211 E-Class, with its AIRMATIC Dual Control system, offered a blend of comfort and dynamic driving. The air suspension struts in these vehicles work in conjunction with the vehicle's electronics to maintain a consistent ride height and adapt to different driving conditions. The availability of aftermarket solutions, such as the Arnott AS-2787, highlights the prevalence and importance of this technology in these specific E-Class models.

Benefits of Air Suspension

The integration of air suspension struts in these Mercedes-Benz models brings several advantages:

• Enhanced Comfort: The ability to adjust air pressure allows the system to absorb road imperfections more effectively, providing a smoother and more comfortable ride compared to traditional suspension.
• Improved Handling: By stiffening the suspension and lowering the ride height, air suspension can significantly improve handling, especially during spirited driving or at higher speeds, reducing body roll.
• Adjustable Ride Height: Drivers can often select different ride height settings, allowing for increased ground clearance when navigating rough terrain or a lower profile for improved aerodynamics and a sportier look.
• Load Levelling: The system automatically adjusts to compensate for changes in vehicle load, ensuring a stable and level ride even when carrying passengers or heavy luggage.
• Consistent Performance: Unlike conventional springs, which can sag over time, air springs maintain their intended height and stiffness, providing consistent performance throughout the life of the component.

Maintenance and Common Issues

While air suspension systems offer numerous benefits, they can also be more complex and potentially more costly to maintain than traditional suspension. Common issues can include:

• Air Leaks: Over time, the rubber air springs can develop small leaks, leading to a gradual loss of air pressure and a sagging suspension.
• Compressor Failure: The air compressor can fail due to wear and tear or electrical issues.
• Sensor Malfunctions: Faulty height sensors can lead to incorrect ride height adjustments or system errors.
• Strut Leaks: The integrated shock absorber and air spring unit (air strut) can also develop leaks, particularly at the seals.

When an air suspension strut fails, it often requires replacement. High-quality aftermarket options, such as those from Arnott, are available and can offer a cost-effective solution. These aftermarket struts often incorporate improvements over the original design, such as enhanced sealing and more durable materials. For instance, the Arnott AS-2787 boasts a multi-ply ContiTech air spring bladder, known for its robustness.

Comparison: Air Suspension vs. Conventional Suspension

To better illustrate the advantages, let's consider a simplified comparison:

Frequently Asked Questions

Q1: Can I convert my Mercedes-Benz to air suspension?

While technically possible, converting a vehicle not originally equipped with air suspension is a complex and expensive undertaking. It would involve installing an entirely new system, including compressors, air springs, lines, sensors, and control units. It's generally more practical to purchase a model that came with air suspension from the factory.

Q2: How do I know if my Mercedes-Benz has air suspension?

Check your vehicle's owner's manual, or look for controls in the cabin that allow you to adjust ride height or suspension settings. You may also hear the air compressor engage periodically to maintain pressure. If your vehicle sags significantly when parked and then raises when started, it likely has air suspension.

Q3: What does it mean when the air suspension warning light comes on?

An air suspension warning light typically indicates a fault within the system. This could be a leak, a malfunctioning compressor, a faulty sensor, or an issue with the control unit. It's advisable to have the system diagnosed by a qualified technician as soon as possible to prevent further damage.

Q4: How long do air suspension struts last?

The lifespan of air suspension struts can vary depending on driving conditions, maintenance, and the quality of the components. However, they are generally expected to last for many years and tens of thousands of miles. Proactive maintenance, such as checking for leaks and ensuring the compressor functions correctly, can help prolong their life.

Q5: Are Arnott air suspension struts a good replacement for my Mercedes-Benz?

Arnott is a well-respected manufacturer of aftermarket air suspension components. Their struts, like the AS-2787, are often designed to meet or exceed OEM specifications, using high-quality materials like ContiTech air spring bladders and custom-valved shock absorbers. They are generally considered a reliable and cost-effective alternative to genuine Mercedes-Benz parts.

Conclusion

Mercedes-Benz has a rich history of incorporating advanced suspension technologies, and air suspension struts are a key part of this. Models like the W219 CLS-Class and W211 E-Class, particularly their AMG variants, exemplify the comfort and performance benefits that this system provides. Understanding the components, benefits, and potential issues associated with air suspension is crucial for owners of these sophisticated vehicles. Whether you're experiencing a fault or simply seeking to maintain your vehicle's exceptional ride quality, being informed about air suspension systems ensures you can make the best decisions for your Mercedes-Benz.