Suitable for Mercedes-Benz
ML-Class W166 AIRMATIC (2012-)
ML250 CDI / ML250 BlueTec ,
ML350 / ML350 CDI / ML350 BlueTec, ML500

GL-Class X166 AIRMATIC (2013-)
GL(S)400 , GL450 ,GL500,GLS500,
GL350 BlueTEC, GLS350 d

Quick detail 

Applicable models:
2012-2016 ML-class, 2013-2016 GL-class - again with adaptive dampening.
2012-2016 fit Mercedes-Benz ML-class
2013-2016 fit Mercedes-Benz GL-class

fit Mercedes ML W166 W/ Electronic Sensor

OE Number:
166 326 05 00, 166 320 01 30, 1663260500, 1663200130, A1663200130,
A1663260500, A 166 320 01 30, 1663200130, A 166 320 09 30,
1663200930, A 166 320 08 30, 1663200830, A 166 320 04 30,
1663200430, A 166 320 19 30, 1663201930, A 166 320 26 30, 1663202630

An air strut with separable air springs
If your vehicle offers a separable air suspension (Audi Allroad A6 C5, Mercedes-Benz W164, BMW X5, etc.), you should regularly (about once a week) lift the car to the maximum position, and remove dirt with a high-pressure cleaner (keep the cleaner at a distance to the air spring about 30 cm/12 inches, otherwise water pressure can damage the air spring). The highest position may vary depending on your model and regulation options. Therefore, please test this by trying the different modes available to you (Sport, comfort, dynamic, off-road) and choose the one that sets your vehicle to the highest position. The dirt will most likely be found under the fold of the pneumatic chambers. If you find a frozen layer of bitumen on the piston guide (the part of a strut on which the air spring is installed), it is recommended to clean it as well. Whenever possible, avoid riding on fresh asphalt, as fresh bitumen mixed with sand immediately results in a build-up of abrasives on the piston and in turn contributes to accelerated wear and tear of the air spring.

Air bags
They are simple rubber bladder that holds air. Air bags are also mentioned to as air bellows. The air bags are located in the middle of the frame of the vehicle and the vehicle axles. Air bags are estimated for weight and pressure capacities.

Components of the air suspension system
An air suspension system generally has three basic components. They are air supply, the air bags and the height control valves. Drier, Air Pump, Control Module, Air Line, Height Sensor, Suspension air bag, Solenoid

Air Suspension Kits

Production cars use set shock absorbers and coil springs, and changing those from stock without ruining the car's ride or handling takes time, patience and expertise. And choosing a suspension kit can be a daunting task. There are a multitude of manufacturers and companies selling a wide range of components in a bewildering combination of quantity and quality.

Added to the mix is the fact that air suspension kits only replace coil springs, and coil springs are part of a larger suspension system. Given this fact, many companies offer total suspension overhaul kits, where everything from tie rods to control arms and shocks are replaced with high-end components designed to maximize what an air suspension system can offer.

However, in general, the most basic kits come with air bags to replace a vehicle's coil springs, along with a compressor and air lines. Most basic kits are a two-way system that can result in heavy body roll. Stepping up the line in price means better components, which means more control and variability, better components, and more speed in making changes.

Buying a kit should not be a casual affair. Owners need to put a lot of thought into what they want from a system. The owner of a classic El Camino show car looking to drop his suspension to new lows would need a different system than a heavy-duty pick-up driver looking for better load capacity and control when hauling tools and building material. Similarly, a race driver would be looking for a different level of performance than the driver of a touring car.

Top-of-the-line kits use a four-way system coupled with an advanced controller. Each air bag is controlled separately, but they're linked together by the electronic controller for dynamic and static control. When choosing a kit, consumers also need to understand the differences between pressure systems and ride-height systems.

Pressure-based systems monitor only the air pressure in the bag. This is fine in most cases when you want to do something like preset a pressure to lower a low-rider at a show. However, adding ride-height sensors into the electronic mix brings the kit to a new level. Ride-height systems monitor how much a car raises and lowers while monitoring the pressure needed to reach each level. Ride height and pressure come into play in performance applications as well as work applications, like keeping suspension up on a pickup truck loaded with a few tons of mulch.