You may need to reset your mpg occasionally. All my mods and I got 23.0 mpg at 70mph cruise set, a/c on. I don't bother intown readings, I like to get on it too bad.
2006 GT Premium, Black with parchment leather IUP, Shaker 500, Side, 5 speed Hurst shifter.
JLT CAI with SCT X-cal 2 Tuner w/ Bama Chips 93 octane tune;Gold 10" Shelby stripes. CDC Ducktail & Classic Chin Spoiler. SS Grill with center light option, 1967 GT 350 badging. SLP Long Tube Headers w/ catted X pipe, Flowmasters American Thunder; FRPP 4.10 gears, Steeda ultra springs & UD Pulleys. BMR Fabrications Panhard Bar, LCA's w/ brackets, A arm support, Strut Tower brace.