I was so torn with the different sounds when trying to decide what exhaust to go with. Finally i found a shop that has been around for about 15 yrs and only does exhaust. (nothing else). So we narrowed it down to 3 mufflers. Cut the exhaust and they slid each muffler on one at a time. I went with a 40 series flowmaster. They put it back together and called me back in for a listen. They then suggested to go back under and cut out the resonator. I agreed. So if you want that nice sound at about 2800-3000 rpm and that rumble at idle and its a 4.0L then Flowmaster 40 series and cut out the resonator.