i just left working at my dealer and while i was there i did many of these recalls. they will bang on the cat and if it rattles they will replace it and if not they will just reprogram the pcm. all it does is set "green miles" for the new cat or reduce excess fuel for the old ones. as far as the muffler goes, you have to look at it from a business stand point, they don't know the cat caused the problem without cutting the muffler open and obviously they can't do that. if they replaced the mufflers then they would get tons of bogus claims of people just trying to get free stuff. as far as the out of warranty thing, all recalls are good after expired warranties and actually your cat has a longer warranty than you think. cats are 10yr 100k miles just most people don't know that and replace them without checking. also if you don't reset the pcm after replacing your cat at home you will decrease it's life by half. hope i'm helping.