Muffracing

Has any one else had this happen. I have a stock exhaust on my 02 T/A and I noticed it was starting to get kinda loud. I crawl underneith and wiggle the pipe and it gets worse. It got worse so I figured it was the flange gasket on the manifold. I get the new gasket, get the car jacked up and look undernieth and the weld on the pipe came off. There was no weld left on the flange and the pipe and cat were hanging on one of the studs. What the hell is that? I'd say GM needs to check thier welders and make sure they are getting better penitration. I TIG welded the outside of the flange and then I did the inside of the flange to smooth it out and give it a little more strength.