Mpg
In one of my exhaust threads I mentioned that I was getting worse MPG's with the Flowmaster vs No Muffler. I have been tracking my fuel ups with Fuelly. Here's some of the results.. Sorry for the sloppiness.
Muffler Removed
January 1
15.3 MPG
January 6
Towed for roughly 200 miles.
14.7 MPG
January 9
16.2 MPG
January 15
Used Tow/Haul mode.
15.1 MPG
AirFilter Cleaned, Muffler Put Back On, PCM Reset
January 22
14.8 MPG
January 30
14.4 MPG
February 5
14.0 MPG
February 9
14.1 MPG
Muffler Removed Again, PCM Reset
February 12
14.5 MPG
February 21
15.2 MPG
March 3
15.6 MPG
Not too sure about yall but I see a trend.
| 
Threaded Mode