I just put on a gibson 9704 Extreme Dual Exhaust on my 04 4.0. I really like it. It sounds just like the wav clip on the wave sight, but I almost never just sit there and rev up the truck. I think it sounds better during driving. Not raspy not ricey. Sounds good. I went gibson because I was once told that flowmaster dont recomend theirs for v6 applications. I was actually told this by Flowmaster them selvs when I was deciding on that or Dynomax on my 93 SHO.
When I started looking at the gibson I got I noticed that it is a flow through type of muffler. I could actually see through it.
Long story short, Sounds good.....Real Good. AND I would do it again.
I offer my truck up for review if you want to come here and see it / ride in it.