As much as I like the looks of the Magnaflow muffler that many go for that addresses the sad factory Y-pipe replacing it with 2 separate pipes entering the muffler, I don't want it for the reason that my Pathfinder is my long haul family car and I don't want the sound that comes with performance mufflers. I also don't want to have to turn up the volume to overcome any exhaust sound.

I do have a Magnaflow cat back system in a car with a main muffler and 2 resonators with 4 tips and it sounds great on that car and that car is fun to drive and drive hard. When I'm in the mood for a proper drive, the Pathfinder sits. The neighbours know I've got exhaust especially at 5:30am when I leave for work. I crawl out as slow as I can as I actually like my neighbours.

BUT

I don't like the factory Y pipe, and I do not want the Magnaflow on the pathfinder. My exhaust seems ok right now, but I want what should have come from the factory on the R51 which is the same design and what I have on my R50 Pathfinder- a 2 in and 1 out muffler configuration. It just makes sense that this is how it should have been, but we have what looks like a win for the accountant and a loss for the engineer with the final design for the R51. I'm sympathetic to the Engineer. I don't like this Y pipe performance loss/cost savings compromise.

The V8 Pathfinder has the right muffler with a 2 in and 1 out design. Has anyone taken that factory OE muffler to a shop and had them modify the piping so it fits the V6?

Or, has anyone taken a Factory or lesser quality Walker Quiet-FlowSS aftermarket Titan or Armada muffler to a shop and had them modify that to fit? They're also a dual in single out. Rockauto shows 0 options for V8 pathfinder mufflers, and in checking Walker's site, they don't list a muffler for the V8 pathfinder.

I looked at the R50 Walker muffler but the piping is smaller on it than the R51 so not a good candidate I don't think. I'm on my second Walker on the R50 and I'm content with it, it lasts about 6 years for me at a fair cost. I'd rather a bigger piped muffler for better flow (I know the quiet ones are still restrictive) so am looking at the V8 Path, Titan, and Armada options as candidate for a customised solution for the V6 pathfinder, for when the time eventually comes that my original muffler needs replacing.

Well, the v8 muffler fits under the Pathy just fine. Get a hold of one, take it to your favorite local exhaust shop and have them make it work.

Honestly, I think the factory "Y" alleged performance loss is a lot less than people think. I went from stock exhaust to DT headers and mid-pipes and the Magnaflow 12580 muffler (2-in/1-out) and other than the drone and noise, I really didn't notice any difference in performance. Yeah, it looks like crap, but do we really have any dyno data that proves there is a significant loss due to it?

Dyno data would be nice. For now, behold the breathtaking Y pipe.

Yeah, it's not pretty. But, can we say it's restricting the exhaust flow? ....Maybe... Some have left the factory muffler and just replaced the actual "Y" with an aftermarket "Y" section that looks more attractive and "maybe" less restrictive?

I installed a Magnaflow muffler and got rid of the restrictive Y pipe about 10 years ago. I left on the stock resonator.
The sound difference is noticeable (and really cool), but not too much. I've never needed to turn up the volume of my stereo because
the exhaust was too loud.
Seems like those that changed or eliminated the resonator didn't like the sound.