I have a flowmaster muffler that we out on my dad's 1991 yj. He drove to town about 5 times, maybe a total of 100 miles before removing it. It is a single in and out @ 2 1/2" diameter. It was professionally installed and removed. I will box it and ship it for a total of $80. Let me know! p.s. it's kinda loud on a 2.5!