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Aero Turbine

1957 Views 11 Replies 10 Participants Last post by  nfd538
I was wanting alittle input on their 4040xl muffler. I know they say you will gain mpg so how much will i gain. And i was wandering how it would sound if i left the cat on. So if someone can give me some info on their experinces with them and maybe some sound clips with a 6-speed, and the cheapest place to buy one. And will this system mount up in place of my factory exhaust?
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I have a 4040xl on the way so I'm eager to get info first hand.


Before buying I did a search and found a few sound clips of the 4040xl and no cat.

I'm planning to leave the cat on to keep the truck from being too loud. I'll see how that goes. I can always take it off if I want more.

I'm planning to put it in place of the stock muffler. The goal is to keep any interior drone to a minimum.
I have the 4040xl....

Left the cat on and I can say that there is a slight increase of rumble at low throttle and you will notice a slight increase in depth idle

At highway speeds as soon as you reach your cruising rpm it does seem to quiet down to the point I think it is almost stock

As for increase in mpg...its just like any new toy, if you can keep your foot out of the skinny pedal you may see a .5 - .75 mpg gain....between the cool hose, muffler and K&N air filter I find myself listening to the sweet sound of lower mpgs..

BTW - when installing you will need a small / short piece of pipe to install inthe stocklocation...less than 6" I believe, local muffle shop welded in mine for under $75...couldn't get dirty for that price

my $.02
I am not sure about mpgs but it did lower my egts
dont belive the MPG.....they are a good sounding muffler at a decent price.... this is where my buddy bought his from Xtreme Diesel Performance - XDP Diesel Power Performance Parts
Great sounding muffler, i have the 4040xl on stock pipe without a cat. Since the stock muffler is offset and the new one is straight through it push up my tail pipe up real close to the bed. I didnt have a tip or anything on it and the noise was crazy loud. It didnt come in contact with the bed but the exhaust sound went under the bed and amplified. I put a tip on to extend it past the bed a little and it sounds great. Not too loud either.
DPP Aeroturbine 4040XL Cat-Back Exhaust Kit 04.5-07 5.9L Dodge Cummins

here is where i got mine, it comes with the pipe to over come the factory muff offset in/outlet.

i put mine on my 06 QC and left the cat. muff swap basically. i loved it sounded great not raspy not to loud but could hear it when u got on it and sounded killer at idle.

MPG well like all these things....to they improve the efficiency yes but dont expect much.
I was wanting alittle input on their 4040xl muffler. I know they say you will gain mpg so how much will i gain. And i was wandering how it would sound if i left the cat on. So if someone can give me some info on their experinces with them and maybe some sound clips with a 6-speed, and the cheapest place to buy one. And will this system mount up in place of my factory exhaust?
had one after i deleted cat. was too loud straight. it was a very good sounding muffler. mpg gain? i have an auto. not too much maybe 1.5 to 2 at most. but i got sick of it being too tame. i did not have cat intact. just straight pipe with this muffler. i went to a single stack str8 pipe. you want to buy my muffler? :rof
offset pipe - can that be bought somewhere?

I saw a cat test pipe on craigslist, is that the same thing?
cat pipe is prob just a str8 piece of pipe. the other over comes the off set inlet outlet of the factory muffler
Although I've got the 4040 instead of the 4040XL, I haven't noticed any changes in performance, but it definitely sounds great! I left my cat on since some states require you to have one.

Dave
I'll have to take a video of mine. I left the cat on, sounds nice at idle and no drone at speed. Its a nice muffler.
I'm woundering if I can use it with a new 4" exhuast system, like one that comes without a muffler.
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