Ok, I found out that I do in fact have the 4.7. Now I am looking at running a dual or maybe single flowmaster 40 series exhaust system and a K&N cold air intake. Are there any other parts or things that I can upgrade to get a few more mpg's? I will be changing my spark plugs and maybe the coils too if they are bad. Please let me know what parts are the best to use in all that I am going to be using i.e. spark plugs, coils, ect. Thanks for all the advice I have been given and will get.

 

If you get a chance, try to listen to a Durango with both a Flowmaster and a Magnaflow. I had a Flowmaster on my Durango with my headers and CAT back dual exhaust, and I hated the drone it created. When it wore out I replaced it with a Magnaflow, and LOVE...LOVE!!!...the deeper notes and muscular gurgle it creates.

I have had the same results in my classic Corvettes, and various other car and truck projects. I always started out with Flowmaster because everyone likes the name...but was so much happier when I switched to Magnaflow. Now I don't even try both...I just get Magnaflow mufflers.

 

I will have to check out the magnaflow site soon. I like the sound of the flowmaster 40, but I also would like to have that classic deep sound of an old school muscle car.

 

Ive put the flowmaster super40, and worst mpg`s. Sound is great for a SUV, i wouldnt put it in a car tough

 

a new exhaust is not going to have any significant effect on MPG, the difference is in how you drive it after in order to hear the sound it makes, just FYI

 

Any opinions on this exhaust, please?
http://www.jegs.com/i/Dynomax/289/17354/10002/-1

I just want a reasonably priced cat back "bolt on" system that
sounds as quiet as possible, but still giving a performance boost.

5.2 .. 318 .. K&N drop in .. New Champion Truck Plugs .. Superchips 93 setting.