theres a rattling noise coming from under my 99 bonneville se.... it seems as when i accelerate and turn its the worse but is still there when i just drive..... seemed like it might been like my exhusast rattling around but its not.... what do you think it could be?

Did you check the heat shield on the catalitic converter?

i didnt but i have a feeling its not something with the exhaust but i will check

Let us know if you find anything. There is also a metal cover that'* screwed in place for teh wires for the O2 sensor. Check that.

when is the last time you replaced the sway bar end links?

I've had them break and come apart. sometimes the washers rattle around if the bottom of the end link didn't fall out.