InsidiousGT

3.73s

So far 1428 miles on it, average of 17.0 over all of those miles. Thats about 70% city / 30% highway. Including some very hard driving and track time.

RandyW

My wife and I went on a 12-day road trip and racked up 4581 miles. We did everything from 400 mile stretches of nothing but Interstate to vigorous driving on mountain roads in Tennessee and North Carolina, much of that being in 3rd and 4th gear. Some city driving, too. The worst tank was 21.08 mpg and the best was 27.04, with the trip average being 24.1. The display in the instrument cluster showed the average as 22.4. I found that when the Miles to Empty was down to 1 mile, there were still about 1.3 gallons still in the tank.

GOS47

3.73 WITH ABOUT 1500 MILES. averaged about 18 give or take .5 ,mostly back roads. I havent done must highway driving in it yet.

Lancel

Thought I should update now with evidence of post break-in. Drive really hasn't changed at all, took a short trip, but it was already up to 15.9 by then. Now it's sitting at 16 MPG even with 1600 miles.

assasinator

if i wanted gas mileage id swap to 2.73's like my turbo 4v has. btw i got 24mpg driving mostly highway at 79mph.

Lancel

The car actually seems to do better if you drive it around 60-70 in 6th gas mileage wise. Just my educated guess though. For a while I swapped the dash screen to the gas mileage scale, watching what kind of driving killed gas mileage and what kind of driving increased it. I generally found that following slow pokes in 6th through hills going 45 was horrible for gas mileage. Requires a lot of gear shifting I think, going from 5th to 6th and back again because FOR SOME REASON everyone wants to drive 40-45 through there, which for me is right at my shift point for 5th and 6th. Very annoying, especially when they don't stay a constant speed, which is common. I should probably learn to just leave it in 5th.

It's sitting quite firmly at 16 MPG now. I'll probably reset it soon.

KonaBlue5.0

While gas mileage should never be the number one reason for buying a particular sports car - why shouldn't it be nice to think about it, as well? Sure, I have a hell-raising 5.0L under the hood, that can paint stripes on any given road for miles should it so choose..but I can also achieve nearly 30 mpg when my foot isn't so deep onto the loud pedal. This car is my cake, and yes, I am definitely eating it, too.

chopperhopper

I installed 3.73 gears in my 2011 6-speed auto and was really worried about mpg. I just completed a 1000 mile trip to N.C. and on the 385 mile return trip, I averaged 24.4 mpg through the country in Georgia. I have long tube Kooks, x-pipe, Roush CAI, SCT tuner installed. However, it is dyno tuned, and if you don't have your tuner set the air/fuel ratio, you are just wasting your time. Mustangs come from the factory on the rich side. You have to set the ratio in the shop, because it takes into account any addons, and gets the mixture right. Don't believe me? Call and ask a shop that knows how to tune a race car.

nite

welcome aboard dave and congrats on the mods; sounds like quite a beast! don't worry about anyone not believing you, as there's a lot of folks here who are well versed on tuning for proper a/f ratios, and it's not at all surprising that the stock tune would be a bit on rich side, as that keeps the motor safe when little johnny get's his grad present and insists on bumping redline 20x a day to show his friends how cool he is.

back on topic... 3.73's, approx 1400 mi, 70 city/30 hwy and i haven't managed better than 19mpg, but then again, i haven't really been trying (still having way too much fun). nice to hear about the capabilities though; gives me one more thing to brag about.

Digital_Synapse

Oh noooo! Did you sell the black stang?!

Overboost

Right now in my 80% city/ 20% highway driving, I'm seeing 17.5-18 mpg on average. In strictly highway driving, with a 78 mph cruise speed, I get around 25 mpg easily.

nite

Yeah, had to do it, Chris... All good though, as I have big plans for the '11; when said and done, it will make the 'ol SGT look like a pile.

Digital_Synapse

wally10

I found that my car is not as fuel efficient as a tree hugging Pee uss or a bark humping fiesta...or a honda sfit....or a fart car....dang....shoulda got a scooter !!

mike05gt

took my 5.0 (3.73) on a 2.5 hr cruise @ 65mph with approx 900 miles on the clock. Vehicle computer showed 26.2 mpg

larthallor

Just picked up my first Mustang (2011 GT Black Premium with 3.31 ratio) 5 or 6 hours ago from the dealership (they stayed late to get it done). The dealership is about 2 hours of 95+% highway driving away, so I decided to try to drive as economically as possible to see how high I could get the mileage. This translated into slow, low RPM acceleration to 65 mph cruising ... punctuated by some face peeling pulls to 80, because, after all, I'm only human.

In any case, as I racked up mile after mile (about 75 overall), the built-in average MPG display kept creeping up until I was running 25.0 mpg. This was on 93 octane from Sunoco in about 65 degree clear weather (the dealer only had 87 octane available, so I passed on the free fill up.)

Any ideas on if being such low mileage was helping or hurting this performance? Is it possible I might see even better highway mileage after the first 1000 miles?

Watchdogg

I am averaging 15-18 rural driving with 3.73 (still under 1000 miles) I got 22 on a 60 mile highway drive with a very heavy foot. Amazing to think about it. I got 10 mpg yesterday on a 5 gallons romping on it on some very obscure Texas hill country backroads yesterday

I do not see how anyone could complain about a car with this level of performance and able to get 20+ mpg. Gets better milage than my truck and if gas prices go crazy my other car is a corolla

Thank you Ford for building this awesome car!!!

Digital_Synapse

Mine is an Accord. Check out my youtube channel for some hillcountry roads.

FLAstangx3

3.73, 5.0, 6sp. 2 weeks young, 850 miles. Ave (so far) 22.2. Variety of driving. Best test rpms under or at 2000 got 25.4. Using 89 octane for now.

Next up, CAI, Tune & Exhaust +93 octane ... then I'll really test her. Not that I care, cause I don't. BUT, the question was asked :-)