I have ppl tell me my truck is pretty quiet, but they were expecting more 'cuz of the stacks. My wife thinks it's too loud (of cource, she drives a Dodge Nitro).
I'm using the muffler I got when I bought my 5'' tb system which I got off ebay from fullspectrumperformance. I contacted the person awhile back about selling just the muffler and replied yes so if anyone wants one.....