Now before I take it back to the dealership to ask them what's up I thought I would ask the experts first.

I bought my truck brand new about 5 months ago and only have 3200 miles on it and have noticed that the max amount of MPG that I'm getting is around 10/11 MPG for city driving!!! I only live about 5 miles away from my work and do very little highway driving so this is all I have to go off of. The truck runs fine with no problems that I have experianced.

Just to give you a little background info, it's an 05 5.4L Supercrew 4x2 with 3.55 LS rear end, only upgrade was a new stereo. I live in the midwest (Illinois) and there are no hills to go up and down, and my driving habits are very grandpa'esk to say the least (e.g. no burnouts, agressive driving, etc.).

Now I have also heard that some of the 04/05's F-150's needed there EEC's reflashed due to some of these issues, but again that's alot of hear-say.

Hopefully one of you can chime in and give me a little insight as to what to do or what to recommend to the dealership.


Thanks for all the help everyone.

Andy

 

I was only getting around 12 maybe in my 04 with just city driving with the 3.73 diff, so I think 11 with the 3.55 is about right.

 

im getting 11 with a lift and the edge

 

05 W/ 3.73LS, with exhaust and I'm averaging 12 mpg city, 16mpg hwy... I expected better..

And I've had the reflash.. (GET IT DONE, makes a difference)

 

The truck needs to break in more, also take it for a run on the highway once in a while. 3.55s in town are killing you, if you plan on doing all city I would invest in gears (4.10) and that will bring up your gas mileage. Also a programer will help some also. I have the Edge and it made a difference in performance and fuel but you can choose the one you like best. I can go on and on but the items I mention will help a lot.

 

I get 16.5 to 17 driving around town with some freeway, some stop and go. I get 19 if it is strictly highway. I do not drive it easily, freeways and highways, 70 to 80 mph, I like to get up and go. I had the reflash at about 2600 miles and it helped my performance significantly, but have no idea about how it affected gas milegage. Since about 2600 miles, I keep records of every drop of fuel and how I drive, so my mileage is not an estimate. I now have 23,600 miles on it. My truck sounds like the same setup you have, Screw with 5.4, 3.55s, 4x2. I do have a K&N drop in and a SIDO Flowmaster, but I don't think they help the mileage at all. If they do, it would be very slightly. I would suggest a reflash if possible and the PCM needs to relearn your driving habits.

 

The mpg's seem about right considering your short driving distance each way. The truck barely gets time to warm up. I'm in the same boat, my commute is a little over 3 miles to work. I get about 11.5 mpg's right now, and it should go up to about 12.5 or 13 as summer approaches (no more winter gas mix). I have the 5.4, 3.73 gears, 4x4 and about 18k miles. I used to have an Airaid intake and Magnaflow exhaust which gave only a 0.5 to 1mpg increase, if any.

 

I have an '05 Screw also, and I get a bit better than that with 4WD and the 3.55LS rear end. I agree that getting a reflashmight help, as will letting the computer adapt to you driving for several thousand miles.

Regearing would probably help, although it's hard to say when that would pay off. Assuming gas at $2.70 a gallon, and assuming you get an additional 3 mpg with the new gears, you'd need to drive 10,000 miles to save $525 in gas, and you'd need to drive 20,000 miles to save $1050 in gas. Whether that would ever pay would probably depend how long you plan to keep your truck and how many miles you drive.

HTH!

 

You'd be amazed at how much better economy can be if you watch how you treat the gas pedal. I was getting 14.3 mpg over a 3 month period with my normal driving habits. I then decided to try for fuel economy. Slower accelaration and more coasting or planning of upcoming traffic. Not trying to beat other drivers to the next light. My economy went up to 16.5 mpg over the next three months. That is no joke.

Another thing to check is your tire pressure. Make sure it's at or slightly above recommended, not below. Your tires actually lose a little pressure in the winter months due to the cold. I always check my tire pressure around Thanksgiving for the upcoming winter.

 

I'd tend to think that is a bit low, but maybe that is what you could expect with the lower gearing. I'm getting 12.5 in Las Vegas driving, which is stomp the pedal on the left, then the one on the right. I play around quite a bit, and am running a supercharger, so I'd expect quite a bit less gas mileage than a stock truck. Every tank I have has several "boosted" runs on it. I'd get to the dealership and ask them what's up.

 

But that takes all the fun out of driving! I am convinced that coasting saves a lot in these trucks. Since we have the drive by wire and computer, the engine is not hooked to the driveline, when we coast, the engine goes to idle and saves a lot of gas.

 

I have an '05 with 10,000 miles, 3.73 gears and the 5.4L. I drive about 95% city miles and average around 14-15 MPG. No hills here.

 

I have 04 reg cab 4.6L 4x4 3.55 6.5ft box with 16k miles on it.. I get 11 mpg with 85% city/15% highway. I keep all shifts under 2500 rpm and I normally dont go over 65 mph.

When I brought the truck home I did all highway averaging about 75mph and I got 15-16 mpg...

Would a reflash do anything for me?
I have heard alot of people say that it had a big difference after and some say that it did nothing...

I have since bought a volant and am going to install it this weekend...

I have thought about upgrading the gears but that seems a little pricey for me at the moment..

How much would ti cost for 4.10's to be installed? Thanks

Matt

 

2004 5.4L 4X4 SCAB w/3.73 gears and 24k miles and according to the message center I get about 12.5 during all city driving.

With 3.55's you should get a little better, but you may want to rack up a few more miles. I don't remember exactly how many miles, but my truck did improve after a few thousand.

 

I'm getting about the same MPG...

Look on the positive side of things... you are only driving 5 miles to work, you are actually saving a bundle on gas over anyone driving 30-40 miles.....

"Things are never so bad that they can't get worse"