ok sorry for all the questions guys im new to diesels and trying to learn about them kinda wanting to do a 4 or 5 inch turbo back but with emmisions not shure i was wondering if makes any sense to do a 4 or 5 in cat back would that still help mpg's or not and secondly was wondering if it would help mpgs if i just took the cat and puffler off the stock exhaust and not half to spend 500$$ so thanks

 

I'm not sure about emissions laws in Wyoming (never been there). But I would say anything that makes your exhaust more free flowing would be something to make your engine run more efficiently. THAT being said, if you were to remove the cat off the stock exhaust, you might cause the computer to throw some codes - Anyone else chime in here?

 

as of now i dont know what the laws are but they dont check us im just shure with the country going green that down the road it will come to them checking us...just wondering my stock exhaust is 3.5" and dont seem worth it to me to do a 4" a .5" bigger would help that much more thinking i might just straight pipe my stock still not shure waiting for others to chime in thanks

 

if you do a dpf back it wont help a thing. i have never regretted dpf delete and smarty. 20 plus mpg.

 

i no for the 2004-2005 duramax's with a free flowing exhaust they throw code numbers 401 & 404 but the sell egr false code eliminator for around $140 but im not sure about the 06's

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was looking somemore and some programmers get rid of the codes for a free flowing exhaust to

 

PPE or EFI Live

 

It may or may not throw codes...

 

i cant say if mine throws codes with the cat deleted, but there is no DPF on the 06 trucks, dont know where that came from

Put on an aftermarket cat back exhaust, but keep the stock system, incase you ever need to put it back on it comes out in two pieces, so you dont need to cut it to get it out, however you do need to fight to get the tail pipe out over the rear axle...

 

thanks i have orderd a 5" MBRP turbo back hopefully it will help with my mpg a little too but it has a muffler on it didnt get the delete pipe maby some day see how it sounds i dont think that little muffler will make much diffrence on the sound anybody have experance with that or not?? thanks

 

5" is overkill for a stock engine and technically, there is no such thing as a Turbo back exhaust. They are actually DownPipe back systems. You can install aftermarket downpipes but they are only 3" dia as there is simply not enough room between the engine and firewall for anything bigger.