not to rain on any parades, but my 2005 4.0 mustang (manual trans) with heavier 18x9 and 18x10 rims, a steel driveshaft, and an 8.8 rear end gets 25-27mpg per tank with my daily commute. in fact my last tank was the best one ive had since i pulled the turbo off 27.2mpg.

my commute is 19 miles each way, about 13 of them on the highway with only about 1-2 miles of the highway being slow (not stop and go, but like 20-35mph).

i do drive like a grandma though.

 

Your honesty is commendable.

 

That is out of the ordinary fuel economy for those cars, most don't do anywhere near that good.

 

even with the turbo i was pushing AT LEAST 21mpg per tank lol. goes to show how often i actually got on it

 

Update ...

Filled up yesterday 416.5 miles / 13.641 gal = 30.53 MPG.

At the time of fill up, computer was showing "36 mi to E" and "29.4 AVE MPG".
Total miles on car to date is 3265.

After a normal and un-eventfull 2.25 hrs of interstate driving Monday, the AVE MPG was dispaying 31.7, the highest it has ever been (I always re-set it when I start this morning trip). Wednesday night when I got in the car to leave, it the was displaying 30.0 MPG ... also the highest for a week, so the potential was there to improve on last week's 30.99 MPG.

But there was a big storm on my way home Wednesday night ... rain was coming down pretty hard in Millwaukee so there was standing water in spots on the interstate so traffic was going pretty slow. AVE MPG's had gotten back up to 30.4 before I hit Milwaukee, but dropped down & settled around 29.6 the rest of the way home. A/C or Def was on the whole way home too, so this did not help either.

Doug

 

Nice update. Since my trip my drives have all been "spirited local" ... and I'm showing 18.8 MPG now. That's just for this tank though. :-/ I hope to get 19.2 on the next one.

 

Update ...

Filled up today ... 354.9 miles / 11.278 gal = 31.47 MPG.

At the time of fill up, computer was showing "29.8 AVE MPG".
Total miles on car to date is 3719.4.

Here is a summary of my commute MPG to date:
WEEK 1: 28.81 MPG
WEEK 2: 29.10
WEEK 3: 29.46
WEEK 4: 30.89
WEEK 5: 30.99
WEEK 6: 30.53
WEEK 7: 31.47

Yes, it is still getting BETTER by the week !!

AVE caculated MPG from new is ... 3719.4 miles / 131.567 gal = 28.27 MPG

AVE COMMUTE only MPG ... 2762.7 miles / 91.719 gal = 30.12 MPG

Doug

 

Excellent, it looks like Ford's MPG computer now calculates about 1.5 mpg low when the previous models of the past 5 years do about 1.5 mpg high. Maybe the next Mustang update they can go right in the middle and get it near dead on. That's good economy for a 300 hp knock out car for sure! Gotta love it.

 

Last week I drove from the Virginia mountains to the Chesapeake Bay. Near the Bay I stooped for a drink and some gas. MPG indicator showed 33.8. I pumped 8.19 gallons and had 278 miles on the trip odometer. I manually did the numbers and got 33.9. Very close! I did go mostly interstate and ran 70-80 mph. Super pleased with the mpg and hp!

 

Jeez Doug, you put a lot of miles on your car! I'd be interested to see what kind of mpg numbers you'd be getting if you had the 3.31s. Any mods planned? CAI/tune/exhaust might up your mpg even more...

 

My last fill-up -- mostly local -- was 21.58 MPG. I have the 3.31 gears. The fill-up before that was 19.60 MPG. Again, mostly local. The one before that was 22.81 MPG.

3400 miles on mine and the lifetime average is: 23.65 MPG. Pretty darn good considering my CTS-V driven similarly was getting about 16 MPG.

 

My commute every week is just over 400 miles.

Me and Jerry would need to swap cars for a month to see what the 3.31's would do !!

Mods to date include:
Custom Front Plate mounting bracket, '94-04 Mustang Cargo Net, CDC Dead Pedal, Lloyds 4-pc carpet Floor Mats, SuperBright LED's (Rear L-P Lights, Trunk Light, & Side Markers), & swapped in S.S. Screws for L-P lamps ... kind of a lame list considering I did $5,300 worth on my '04 !!

Maybe a K&N filter since they are available (thanks to Ford for making it the same as the 5.0L).

I've also got to spend around $1,200 on a set of 17" snow tires/wheels by November ... ouch !!

I'll look into a flash tuner but want to wait until next summer ... give the programers plenty of time to tweek their programs on cars other than mine. Really hoping someone comes up with an adaptive tune so it can get the most out of whatever octane fuel is put in the tank. As we all know, Ford does it with the 5.0L and the 3.7L supposedly has all the same engine sensors that are needed so I don't see why not.

Doug

 

I'm averaging around 45 MPG --- in my Prius.

Don't expect to do as well in my 5.0 of course, when it arrives. But between the Mustang and the Prius (which I'm keeping), I should be averaging around 33 MPG.

 

Update ...

Filled up today ... 410.3 miles / 12.956 gal = 31.67 MPG ... a new best.

At the time of fill up, computer was showing "54-MI to E" and "29.9 AVE MPG".
Total miles on car to date is 4692.4.

Here is a summary of my commute MPG to date:
WEEK 1: 28.81 MPG
WEEK 2: 29.10
WEEK 3: 29.46
WEEK 4: 30.89
WEEK 5: 30.99
WEEK 6: 30.53
WEEK 7: 31.47
WEEK 8: 31.00
WEEK 9: 31.67

Yes, it is still getting "a little" BETTER by the week !!

These past two weeks I had the MAX-A/C on quite a bit too, so maybe I could of hit 32 without.

AVE caculated MPG from new is ... 4692.4 miles / 163.926 gal = 28.63 MPG

AVE COMMUTE only MPG ... 3583.1 miles / 118.03 gal = 30.36 MPG

Doug

 

Tried something new this week ... had 30 miles on it from driving around town, and decided NOT to top it off Sunday night. Figured I've been seeing around 50 MI to E when filling up each week, why can't I do this extra driving at the begining of the tank ??

Filled up today ... 442.4 miles / 14.798 gal = 29.90 MPG.

At the time of fill up, computer was showing "4-MI to E" and "28.6 AVE MPG".
Total miles on car to date is 5134.8.

There was some pretty heavy rain Monday morning and had MAX-AC on most of the week (hot & muggy high 80's to mid 90's), so this was not too bad.

O/A ave. MPG since new is 28.73 ... but O/A ave. since I 1st broke 30 MPG 3100 miles ago is 30.20 MPG.

I'm real happy with these results.

As I've broke 5000 miles, I'm going to do my 2nd oil change this weekend and switching over to Mobil 1 Full-Syn. Did 1st change @ 1500 mi w/ factory Motorcraft Syn-Blend back in.

Doug

 

**** now you guys got me wanting to do this as well, just filled the tank last night, guess ill have to keep my records as well now =)

Orange3 -- Very impressive. Whats your average speed on the highway though?

 

If say anything good about that thing besides the MPG, I'm bringing the IHPC down on you

Look at my sig for what that stands for

 

On Wisconsin I43 & I94, cruise is set @ 75 MPH in 65 zones and 65 MPH in 55 zones. But once I get over the border into Illinois I keep up with the faster traffic which is typically 75 but varies between 65-85 MPH ... all 55 zones. About 90% of my weekly commute is interstate; about 70-80% with cruise on.

I do have the 2.73 gears though, so at 75 she purrs right under 2k RPM's.

Doug

 

Yeah, my last tank was 22.4 MPG. O/A average is 24.35. Total miles: ~5,500. Getting ready to fill up again. Expect this tank to be below average.

The only difference between Doug's car and my car are a) I have the 3.31 gears and b) my right foot is heavier. I also have more traffic and more hills.

 

Very nice, i was actually expecting you to say you drive 55 in the 65 zones... lol

Well, I'm going to run this same test you have been running. I'm a little over 3.5k miles now so i think the engine is broken in enough to get a good reading of what it should maintain. Just going to be a lower number for me unfortunately because i live in Cali with a bunch of retards and immigrants who don't know how to drive >_< But I'm going to try and see if i maintain 30 MPG average