V8StickConv

I have a 2005 GT convertible, black/charcoal, 4.6 5-speed, dead stock except Flowmaster mufflers. I drove home to Virginia from Charlotte, NC. It was about a 300 mile trip. I was driving about 70-80 mph, depending on speed limit. I got about 20 mpg highway on 87 regular. The factory listed 23 mpg highway. Is the factory spec just for really conservative driving, i.e. 60 mph everywhere? How does my 4.6 mpg highway compare to yours?

BTW, people pull over to let my Mustang go by. It's an act of respect.

cruisin5268d

Fuel economy can go down over the years. How many miles on the car? Driving 80, especially depending on your gearing, will give you 20 mpg.

"BTW, people pull over to let my mustang go by. It's an act of respect." Oh wow, please, allow me the honor of kissing your feet. I beg of you.

danzcool

I average 13, but mine is not exactly average...
But the EPA highway is pretty much extremely conservative driving, basically get on an interstate in a flat area after filling up and slowly accelerate to 65 and drive that until empty, keeping the RPMs as low as possible.

PNYXPRESS

I was able to consistently get 27-31mpg running 70-80mph in my 08 with the only mods as muffler deletes and k&N CAI and using midgrade fuel. with a bbk cai and tune it still gets 23-26mpg with 93 fuel.

JFitz

With 93 and a "off the shelf" tune from brenspeed (read sig for mods) I average about 21-22 a tank. If I'm concious of it and keep my speed down (meaning I leave on time for work) I can get 23.

All highway mileage on long trips I've gotten 26.

smokievol

Charlotte to where in Virginia, west into the mountains would drop that MPG easily. Going East to Richmond I would think you would have done better.
I get 24 on HWY taking it easy....70 to 80 would drop mine to 20 I bet.
Thats with a SC.

V8StickConv

Thanks for the tuning info.

Before this car, I had a Dodge Intrepid. People did not pull over to let that car go by. There's no need to kiss my feet, LOL. They don't respect me. People let cars they respect go by. That's a nice thing in a Mustang.

V8StickConv

The drive was Charlotte to Richmond, so the terrain was pretty much flat. My car has 31000 miles. My guess is that it needs a basic tune up to begin with. What spark plugs do you recommend?

ghunt

I drove my car out to Ohio for my cousin's wedding over the summer with the mods in my sig, and my mpg average at the end of the trip was 25 mpg. Nice and flat out there.

At the time the car had about 75K on it, and as far as I know it still has the factory plugs.

Rudolph Hucker

22 to 26 mpg for me..
only ever driven on main roads..