The piece right after the cat flange looks like a muffler yet there is one in the back under the trunk as well. Iv been doing a lot of research and Im not coming up with much other than random mufflers for sale. Mine is an 03 FWD non turbo and that piece will need to be replaced.

 

Just measured it, its 22 inches long and the diameter is about 5 inches. I will be picking one up from somewhere because this is causing a leak and I think its also causing a squeal under a load (when first turned on and when accelerating, no other time)

 

The one under the trunk is the muffler, after the cat is the resonator. What kind of leak were u talking about? Is ur muffler coroded/rusted up?

 

The resonator is falling apart at the edges due to some rust, I cut an after market one out of an S80 at a junk yard for $10 and it looks brand new so I hope it works. Thanks.