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2 Mods killed my mpg?

Justin Nachazel

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1badtie Enthusiast

1badtie

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Drone would be hearing the hum of exhaust while driving. I also have a pretty heavy chopper sound now that I changed out to a 3" pipe. Might do the range disable now to get rid of the chopper. I'm going to give it a couple weeks and see if the mpg comes back up. It could have just dropped drastically from speeding around and testing it. Easier to plummet with mpg readings than it is to rise lol

I also put in a 3" pipe in place of the 2.75" stock wish I would of stayed stock size pipe bc of the loud chopper noise I get now. I also think a 2.75" pipe would sound better

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Justin Nachazel Enthusiast

Justin Nachazel

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I also put in a 3" pipe in place of the 2.75" stock wish I would of stayed stock size pipe bc of the loud chopper noise I get now. I also think a 2.75" pipe would sound better

 

I agree with you. That being said Im hoping that by doing the J pipe bypass that it will take care of the copper sound.

schmolf4 Enthusiast

schmolf4

Posted
Posted

I replaced my factory muffler with a flowmaster 40 series muffler in which I have removed the flapper completely. When I installed the muffler, I had removed the resonator at the end of the exhaust which in turn made the exhaust have a very bad drone in v8 and in the v4 mode. I drove it for a couple of weeks to see how I liked the sound but after those 2 weeks, I re-welded the resonator back on. There is still a small amount of drone but it is something that I can live with, plus the way it is now you dont have to turn the radio up so loud to cancel out the drone.

cato Enthusiast

cato

Posted
Posted

 

2) The DeeZee side steps might have actually been helping with airflow around the truck since I'm keeping the air dam, by switching to low profile AMP Powersteps It creates more air turbulence around the truck.

 

 

I doubt it's this...

Spurshot Senior Enthusiast

Spurshot

Posted
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I doubt it's this...

Agreed. Nothing about steps would make a measurable difference in mileage.

Justin Nachazel Enthusiast

Justin Nachazel

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Agreed. Nothing about steps would make a measurable difference in mileage.

 

I agree also. I was just shooting in the dark for an answer lol

Spurshot Senior Enthusiast

Spurshot

Posted
Posted

The three inch lift is definitely a drag inducing mod. But I would not guess it would be 5mpg unless you had big tires as well. I have a 5.3 with 12.50x33 mud tires, camper higher than the cab, 1 1/2" level and I can get 15+mpg at 80+mph

Spurshot Senior Enthusiast

Spurshot

Posted
Posted

Has anyone been under the hood around the time the mileage changed? Check all hoses and electrical connectors. Hook it to a code reader.

Justin Nachazel Enthusiast

Justin Nachazel

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Has anyone been under the hood around the time the mileage changed? Check all hoses and electrical connectors. Hook it to a code reader.

That's a good idea. Nobody has been under the hood though. I'm not throwing any check engine lights either and I have stock tires. The only thing I can think is the exhaust has too much back pressure with the flapper installed before the muffler but other than that idk :/ the 3in causes drag I know but I should at least be getting better mpg considering the exhaust should breathe better right? Definitely not worse mpg.

Madcow2020 Enthusiast

Madcow2020

Posted
Posted

Disconnect the battery to reset the computer to learn the changes. This is a good idea after a CAI or exhaust modification. Then drive the the truck for a week and see what your MPG do.

 

 

Sent from the future via a wifi time portal.

Justin Nachazel Enthusiast

Justin Nachazel

Posted
  • Author
Posted

Disconnect the battery to reset the computer to learn the changes. This is a good idea after a CAI or exhaust modification. Then drive the the truck for a week and see what your MPG do.

 

 

Sent from the future via a wifi time portal.

Ok I just disconnected the battery and reconnected it. I will report back soon with my findings. Thank you for the advice!

Justin Nachazel Enthusiast

Justin Nachazel

Posted
  • Author
Posted

Disconnect the battery to reset the computer to learn the changes. This is a good idea after a CAI or exhaust modification. Then drive the the truck for a week and see what your MPG do.

 

 

Sent from the future via a wifi time portal.

So far it's starting to look like this was the right answer. I'm back up to 20 miles per gallon :-) i'm going to give it a couple days though and I will report back on findings. Thank you again!

Justin Nachazel Enthusiast

Justin Nachazel

Posted
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Any update?

 

 

Sent from the future via a wifi time portal.

 

Glad to report 21mpg right now :)

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