Installed New Muffler

[trucc_boi]

just got 20.2 mpg on average for this last trip driving through hilly central/west texas.

 

got a nnbs 07 with a 5.3l with AFM.

 

just added a magnaflow 18" with a side-exit tip.. i was getting about 19 or so before the new muffler.

 

i got a k&n (just the filter), tonneau cover, and a custom tune in the future..

 

just looking for what else or recommendations y'all could make for better fuel economy.. I want to keep the AFM (the exhaust still sounds good when it goes to 4cyl mode). really looking for ideas on making my own intake or the best air filter i can get.

 

i am really happy with 20 mpg, but i am just wondering if there's any recommendations y'all can make to help me get the most mpg possible.

 

thanks in advance

[BigBlueLB756]

Don't know if this will help, but might give you some ideas. Look under:

Advanced & Technical Discussion

Engine and Powertrain Tech - page 2

Cheap Factory Air Intake Mod

 

There's some potential for getting fresh air directly to your K&N.

[jro909]

i'm averageing about that on the highway with my Gen3 5.3, no mods..the easiest way to conserve fuel is by driving like an old bag, second being blackbear tune...cold airs and mufflers don't big enough dent to gain anything

[66nova]

I hate to burst any bubbles here, but your muffler is not responsible for your mileage.

 

The best bang you are going to get for mileage is a Black Bear or other custom tune.

 

With a light foot you should be able to get 20+ mpg (highway) on a regular basis on a stock GMT900.

 

It's not really a fair comparison when you look at GMT800 vs GMT900 mpg because the GMT900 trucks are a lot heavier then the equivalent GMT800.

 

All of your mods are good ideas, just don't expect a lot of gain with any of them. Crap, GM release a XFE model silverado that is only rated at 1 mpg more then the non XFE and it has a different tune, CAI, Bed Cover, lower ride height, low rolling resistance tires and a few other things I cant think of.

[hockeypro1411]

I hate to burst any bubbles here, but your muffler is not responsible for your mileage.

 

The best bang you are going to get for mileage is a Black Bear or other custom tune.

 

With a light foot you should be able to get 20+ mpg (highway) on a regular basis on a stock GMT900.

 

It's not really a fair comparison when you look at GMT800 vs GMT900 mpg because the GMT900 trucks are a lot heavier then the equivalent GMT800.

 

All of your mods are good ideas, just don't expect a lot of gain with any of them. Crap, GM release a XFE model silverado that is only rated at 1 mpg more then the non XFE and it has a different tune, CAI, Bed Cover, lower ride height, low rolling resistance tires and a few other things I cant think of.

 

Is it true that they have 3.08 gears?

[66nova]

I hate to burst any bubbles here, but your muffler is not responsible for your mileage.

 

The best bang you are going to get for mileage is a Black Bear or other custom tune.

 

With a light foot you should be able to get 20+ mpg (highway) on a regular basis on a stock GMT900.

 

It's not really a fair comparison when you look at GMT800 vs GMT900 mpg because the GMT900 trucks are a lot heavier then the equivalent GMT800.

 

All of your mods are good ideas, just don't expect a lot of gain with any of them. Crap, GM release a XFE model silverado that is only rated at 1 mpg more then the non XFE and it has a different tune, CAI, Bed Cover, lower ride height, low rolling resistance tires and a few other things I cant think of.

 

Is it true that they have 3.08 gears?

 

 

 

Yes with the 6 speed transmission