I'm all broken in now, 4,900 miles on a '07 GT 5 speed 3.55 vert, I'm averaing 20+. Basically haven't been running a/c at all lately. I generally do one or two highway days to work per week, the then the rest is weekends in the city. I'm more than pleased with the mileage.

 

I get 300 miles per tank (highway/street mixture), but I can squeeze out about 310. I baby my car..... shifting at about 1200 RPM and run my A/C from time to time. I have been getting about 21 MPG avarage lately (hgy/cty mixture).

I noticed getting ALOT better mileage with a K&N drop in filter!

This is my daily driver, so it's not modded much and you can expect to lower the MPG quite a bit with mods and a tune (the main reason, you are having more fun driving it harder).

My mods are... No Mufflers, Eibach Sportline and K&N stock replacement drop filter.

I drive a viper too, so thats one reason I can baby my stang like I do (It's NOT the race car).

 

When I rented a GT-H it said it was doing over 24 MPG, I was really surpirsed.

 

Changed the oil Friday befor driving to Minneapolis to see my daughter at school. Switched to 5W20 pure synthetic. Cruising at about 78-80, we got 24.5 mpg.

 

I am averaging about 22 on the highway, and 14/15 on surface streets.

Can't help but have my foot it in a bit though around town with the Series VI under the hood....

 

My daily commutes of 15.5 miles yields 21 mpg on average. The average speed indicated is usually around 34 mph, thank god for averages. On a side note a 2 hour cruise to Orlando top up yields 24mpg. Not bad for a 14 month old car which just broke 10k.

 

That would put you around Tampa if you are to the west..... I wonder if you are the one I have seen on I-275......

I cruise I-4 to Lakeland with the air on at 75 and get 24.5 MPG according to the little tell all screen.