Have noticed lately that it feels like the front end of my 2012 GL 450 is bouncy. It has the airmatic suspension. Neither side of the Airmatic seems to be losing air or deflating/lowering when the car is off. But the car definitely feels more bouncy/less control, backroads and expressways, slow speeds and high speeds. Are there other suspension components, struts of some kind, up front that might be causing this issue if airmatics haven’t failed? Vehicle has 138,000 miles on it.