I had 2 leaks where the Y pipe connects. The muffler shop said they can't weld since the coating is there. I tried the aluminum foil trick and it seemed to work perfectly. I got 2 cheap clamps and folded up a 1 foot by 1 foot piece of foil until it was 1" strip and wrapped it around the pipe. I then put a clamp on both sides touching and tightened them down. Only 1/32" is showing so it looks as good as gheto can. The noise under the car almost went away so maybe so did my false knock. Thanks to those that gave me the idea. I just wanted to give a little more detail and say it works great.