I have dual Flowmasters on my '52 Chevy pickup streetrod and they have a nice rumble sound.I recently bought a 2005 Nissan Frontier KingCab SE 4x4 with the 4.0 V6. My friend can get me a deal on Flowmaster 40 series with 3 1/2 tip. I dont know anything about exhaust but what will my truck sound like with this on it?
I just put an X-Pipe and dual exhausts with Magnaflows on my 4.0 V6 2005 CC and kept the 2.25" piping and it really improved the performance. The key was removiong the factory Y-Pipe, as it really sucks!
I would suggest that you first replace the factory Y-pipe with an X-Pipe and dual exhausts or buy a new aftermarket Y-Pipe and keep the single exhaust. I think either way will be an improvement.
Merry Christmas and Semper Fi from one Devil Dog to another!