I just got my Durango about two weeks ago, and I am ready to give it a little better sound.

I have seen that it has the cat followed by a muffler and resonator. What is the diameter of the pipe leaving the cat, and is it the same entering it?

Thanks

 

I think the diameter is 2.5 I don't think it is 3in and I would go with a flowmaster 70 series.

 

DO NOT GET THE 40 SERIES. I bought my Durango with a custom Flowmaster 40 series muffler and dual exit.

Sounds good at idle and mild throttle. you should hear the f'ing thing though when at WOT.


I've had better luck with Magnaflow products. Flowmasters (mine current one included) tend to drone on the highway.

here is a startup clip of my durango

 

I agree do not get the 40 series I have it on my k5 blazer and sounds good but I wouldn't use it on these newer motors. The 70 series is an suv muffler its almost the same size as the stock and does not have that drone on the high way at cruising speeds like other mufflers do. A good thing to remember when choosing a muffler is the smaller the muffler is the louder it is and it will probably not sound good a cruising speeds. The 70 series is also designed for the displacement on demand engine and sounds great.