I had the same exhaust problem so I got a new cat and that fixed most of the problem. But after a while I noticed it again so I brought it back to the exhaust shop, they put it on the lift with me there and it turned out to be the O2 sensor. The shop told me that this is a common problem on Chevys. I have a 2000 with the 3.8. Mine makes a lot more noise when it's cold, then gets better once the temp raises. Maybe this will help...

 

thats what the busings are for. in the shift linkage

 

ill check her out. ive got a new "high flow" cat for it... or straight pipe but its whatever. i jus aint got it put on yet.

 

The shifter on your transmission is pinned on to the housing and that housing bolts on to your tranny. I know they can eventually become loose, which can cause them to vibrate more when you put the car under load or give it full throttle at low rpms

 

what would be the easyest way of going about thighting that.

 

Yeah I agree heat shield on the cat. But it could be the cat itself is lose or jiggling about. Did this car rattle when you bought it or after you got it. If it started after you got it then did you hit and decent bumps? You, now that I think of it, could also have broken a clamp and/or losened the mid pipe.