The air suspension struts in the Mercedes-Benz G-Class W465 are a crucial part of the vehicle's suspension system, providing enhanced comfort and performance. The G-Class W465, particularly in its off-road versions, utilizes air suspension to offer an adaptable ride height, improved ride comfort, and superior handling across various terrains.

Here’s a detailed overview of the air suspension struts on the G-Class W465:

Key Functions of Air Suspension Struts:

1. Ride Comfort and Handling:
   • The air suspension struts help smooth out bumps and rough roads by providing a more comfortable ride. Unlike traditional coil springs, air struts use air bags that adjust the firmness of the suspension according to driving conditions, allowing for better shock absorption.
2. Adjustable Ride Height:
   • One of the standout features of the air suspension system is its ability to adjust the ride height of the vehicle. This feature is particularly useful for off-roading, as the vehicle can raise or lower its suspension for better ground clearance or easier access when getting in and out.
3. Load Leveling:
   • Air suspension struts help maintain a level ride height, even when the vehicle is loaded with passengers or cargo. They adjust automatically to keep the vehicle balanced and level, preventing sagging and improving overall handling.
4. Improved Off-Road Capability:
   • On the G-Class W465, air suspension struts enhance the vehicle’s off-road performance. The adjustable ride height allows for greater ground clearance, helping the vehicle navigate obstacles, uneven terrain, and harsh environments.
5. Enhanced Towing Capability:
   • Air suspension also helps when towing heavy loads. The system can adjust to keep the vehicle level, improving stability and safety when carrying heavy trailers or loads.

Components of Air Suspension Struts:

1. Air Spring (Air Bag):
   • The air spring is a flexible rubber bag filled with compressed air. It replaces the traditional metal spring found in conventional struts. The air pressure inside the air spring determines the firmness of the suspension and, consequently, the ride quality.
2. Shock Absorber:
   • The shock absorber is integrated into the air strut to control the compression and rebound of the suspension. It helps dampen the motion of the vehicle and prevents excessive bouncing or sway.
3. Height Sensors:
   • Air suspension struts are equipped with height sensors that monitor the vehicle's ride height. These sensors provide feedback to the vehicle’s control module, which adjusts the air pressure in the air springs to maintain the desired height.
4. Compressor:
   • The air compressor is responsible for maintaining the correct air pressure in the air springs. The compressor draws in air, compresses it, and sends it to the suspension system. It adjusts the pressure as needed, based on feedback from the height sensors.
5. Air Lines and Valves:
   • The air suspension system uses a network of air lines and valves to distribute compressed air to each strut. These components work together to adjust the air pressure in the system, allowing for ride height adjustments.

Common Issues with Air Suspension Struts:

1. Air Leaks:
   • Over time, the rubber air bags can become worn, crack, or develop holes, leading to air leaks. This can cause the vehicle to sag or fail to maintain the desired ride height. The compressor may also work harder to compensate for the loss of air, leading to premature wear.
2. Compressor Failure:
   • The compressor is a vital part of the air suspension system. If it fails, the suspension may not be able to adjust the ride height, and the vehicle may sit lower than normal or fail to raise for off-road driving.
3. Faulty Height Sensors:
   • If the height sensors are malfunctioning, the vehicle may have trouble adjusting the ride height. This can lead to an uneven ride or difficulties when trying to raise or lower the suspension for off-road conditions.
4. Air Suspension Warning Light:
   • If there’s an issue with the air suspension system, such as an air leak or compressor failure, a warning light may appear on the dashboard, alerting the driver that the system needs attention.
5. Sagging or Uneven Suspension:
   • Over time, the struts may wear out or lose their ability to maintain proper air pressure, resulting in sagging or uneven suspension. This can affect both the vehicle's ride comfort and handling performance.

Symptoms of a Faulty Air Suspension Strut:

• Sagging Ride Height:
  • The most noticeable symptom of a faulty air suspension strut is a sagging ride height. If one corner of the vehicle sits lower than the others, it could indicate that the air suspension strut is failing or losing air.
• Uneven Ride Quality:
  • A faulty strut may cause the vehicle to feel uneven, with one side being much stiffer or softer than the other. This can lead to an uncomfortable or unstable ride.
• Suspension Warning Lights:
  • If the vehicle detects an issue with the air suspension system, it may trigger a suspension warning light on the dashboard. This is often accompanied by an alert to the driver to check the suspension system.
• Compressor Running Continuously:
  • If the air suspension struts are leaking or not holding air, the air compressor will run continuously in an attempt to maintain pressure, which can cause it to overheat and fail.

How to Inspect and Test Air Suspension Struts:

1. Visual Inspection:
   • Check for any visible damage, wear, or leaks on the air spring or strut components. Look for cracks in the rubber air bags or any visible signs of punctures. Inspect the air lines and valves for leaks or damage.
2. Listen for Air Leaks:
   • When the vehicle is turned off, listen for any hissing sounds that may indicate an air leak. This can help pinpoint the area of the system where the problem is occurring.
3. Check the Ride Height:
   • Use a measuring tape to check the ride height of each corner of the vehicle. Compare the measurements to the manufacturer’s specifications to ensure that the suspension is maintaining proper height.
4. Test the Air Compressor:
   • The air compressor should turn on when the vehicle is started and should not run continuously. If the compressor runs for an extended period or you notice the vehicle is not raising, it may be a sign of an issue with the compressor or air struts.
5. Inspect the Height Sensors:
   • Ensure that the height sensors are functioning correctly. You can often perform a diagnostic scan using an OBD-II scanner to check for any error codes related to the suspension system.

Replacing Air Suspension Struts:

If the air suspension struts are found to be damaged or faulty, they will need to be replaced. Here’s an overview of how to replace them:

1. Order Replacement Struts:
   • Be sure to order the correct air suspension struts for your G-Class W465 from an authorized dealer or automotive supplier. Ensure the part numbers match your model year.
2. Lift the Vehicle:
   • Safely lift the vehicle using a jack and secure it with jack stands. Remove the wheels to access the air suspension struts.
3. Disconnect the Air Lines:
   • Carefully disconnect the air lines connected to the strut. You may need to release the pressure from the system before disconnecting the lines.
4. Remove the Strut:
   • Unbolt the strut from its mounting points. In some cases, you may also need to remove additional components such as the shock absorber or suspension linkages to fully remove the strut.
5. Install the New Strut:
   • Position the new air suspension strut into place and bolt it securely. Reconnect the air lines and ensure that they are tight and free from leaks.
6. Reassemble and Test:
   • Reassemble any components that were removed and lower the vehicle. Test the new air suspension strut by turning on the vehicle and checking that the suspension raises to the correct height. Listen for any unusual sounds or leaks.

Conclusion:

The air suspension struts in the Mercedes-Benz G-Class W465 play a vital role in providing ride comfort, off-road performance, and vehicle handling. Over time, these struts can develop issues such as air leaks, compressor failure, or height sensor malfunctions. Regular maintenance, including inspecting the struts for wear and replacing damaged components, ensures that the air suspension system continues to perform optimally and contributes to the overall performance and comfort of the vehicle.