Originally Posted by djpathfinder

Does it vibrate all the time or intermittently? I had a vibration that was constant no matter the RPM...if you read my earlier posts from a couple of weeks ago, you'll see I found my rattle was caused by loose O2 caps. Make sure those are tightened. Do you have the stock exhaust? If so, make sure the heat shielding isn't loose or coming in contact with anything else. If the connections (flanges) are seated properly, bolts tightened and there's no exhaust leak, then they should be fine. Is any part of your exhaust contacting other parts of the car (e.g. sway bar)? Just a few ideas...hope it's an easy find and fix.