I've just recently purchaced a georgeous BLK/BLK '97 STS (my 3rd Seville) looks good ....sounds like a old ford truck rattling down the rough city streets. It has 52k and has all the papers, shows nothing being done to suspension. My first thought was bushings (sway bars etc.) but after reading threads on this forum about air ride this and knuckles that I'm confused. I put new tires on it and had a 4 wheel alighnment and the I hear the air pump working, it's set at the proper height. So I ruled these factors out. And what would make the rear sidestep when hitting a bump ? Can anyone offer advice ? And if it turns out to be bushings (sounds cheaper than anything else) are they available in polysomething aftermarket/performance or do I have to go to Cadillac ? And has anyone paid to have them replaced and what is a ballpark figure I would be looking at. I used to bust my own knuckles and would have done this kind of stuff but I'm old and have a real bad back so have to pay the man.