AIRMATIC Suspension – The Day Will ComeBy Jason Burton
- February 26, 2016
- Hi-Line Stories
- Posted by Hi-Line Automotive
- Comments Off on AIRMATIC Suspension – The Day Will Come
When you come out to your Mercedes-Benz with AIRMATIC suspension and it looks more like a slammed lowrider on one or multiple corners and your instrument cluster is displaying the message “Visit workshop” with the image of a vehicle and an up arrow you have a problem. More specifically you have a ride height issue. If this does happen to you the car may still be safe to drive as long as the air suspension raises itself back to its normal ride height; if it cannot then the vehicle will have to be towed. It is important if this does occur to repair the fault soon and not keep driving the vehicle with the issue as it will only get worse and can put excessive wear on the AIRMATIC pump often requiring its replacement in addition to the other failing components.
Modern Mercedes-Benz use one of three suspension systems. A “traditional” coil spring and shock/strut setup, AIRMATIC which is a pneumatic or air based system, and ABC (Active Body Control) which is a hydraulic system.
The AIRMATIC system we are discussing here is relatively simple consisting of an air pump, air lines, air spring and shocks or air struts, and some fancy electronics to make it all work. While the pump can fail the most common failure point is normally one or more of the air springs or struts.
Most AIRMATIC vehicles will use the system on all four corners of the car. Some examples of full AIRMATIC suspension systems can be found on all non-AMG S-Class Mercedes models from year 2000-present as well as GL models. Other models offer it as an option such as the W211 E-Class and W164 ML, with some models offering the system only on the rear. Specifically in this case let’s look at the GL450 model.
The GL450 pictured here had a failure of one of the rear air springs which are much more common to fail than the fronts. The bad news? If one side in the rear fails the other is close behind it. Hi-Line suggests replacing both sides if one has failed since the other side most likely will as well within a few months. The good news? The rear air springs are separate from the shocks unlike the front strut arrangement which means they cost less than the front ones which are considerably more expensive.
There is other good news. Considerable cost can be saved these days by not using Mercedes branded parts. Arnott manufactures replacement air springs/struts for substantially less than MB ones. They even use Continental rubber for the bladders (good German rubber!). The parts are redesigned from the original addressing the weak points and allowing them to perform much better than the originals. Arnott also supplies a lifetime warranty on all their parts which you won’t get from a Mercedes OE part.
So if you find your car is listing like a sinking ship or looking like an elephant is sitting on one end of it in the morning you may have an AIRMATIC issue and your MB dealer may not be your best solution to the problem.