i own a 2003 hummer with the air ride in the rear but ever since i lowered it when ever i go 65 + it starts to shake really bad like if the body is going to come off anybody know what this could be ? does it have to do with the airbags not fully inflated ?

 

hi I also have a 2003 and had a problem with the bags and compressor my bags went flat and would not stay up it rode real ruff like this when bags were down it had a loud thud or clunk but not what u are describing !! But when lower like that your exhaust could b hanging up or banging the rear axle were it goes up and over it ?? I had the dealer quote me on replacing the system and they wanted my first born like 5,500 bucks so I ended up lifting it 6 inches with a bds lift kit air bags are gone and I replaced with coils and the whole kit was only 3500 bucks cheaper than just fixing my air bags... Other than the 40x13.5 mickey thompsons and 20 inch american racing rims of course they cost a pretty penny around 7 thousand but I'm so glad I hadn't just fixed the bags ....
Not sure if any of this will help but good luck !!!