Mine is getting 18 MPG, 4x4 screw 3.73. I AM driving it pretty hard passing people often and alot of city miles but curious if it should go up after 3k miles like some have suggested.

 

Not sure if I have seen definitive proof either way yet

 

My dealer said dont watch the fuel economy until you have a few tanks through. Anyway I am at 2000 miles 4x4, 3.55 and getting 22 mpg, 90% hwy driving between 50 - 70 mph, I cant see it getting much better but if it does great!

 

There are too many variables to compare fuel economy from one truck and driver to another. Here are some factors to consider:

- Highway vs. city
- Terrain
- Rate of acceleration
- Cruising speed
- Load
- 2WD vs. 4WD
- Axle ratio

But the biggest difference is you. If you want better fuel economy, stay on the highway and off the throttle. It's that simple.

It is normal for fuel economy to be slightly worse for a new vehicle. As components break in, there is less friction. But it's so slight, that it's not worth mentioning.

 

I don't believe there is anything that tells the compurter to run rich for 3k. If there is, I haven't seen it. The two quotes above are what I believe and have seen with my truck.

 

Think about this, what benefit would there be to by dumping extra fuel into the motor? Some 2 stroke motors do this to provide extra lubrication during the break in period. The EB is a 4 stroke, what's the benefit?

You might see a small gradual increase due to the motor breaking in and parts loosening up. On my EB this seemed to happen till around the 5000 mile mark.

 

When I was into performance boats with Mercruiser IO's, it was said that the first fifty Hrs. the ECM would tell the engine to run rich. You could see black soot on the stern (rear) after a day on the water. I think it lets the engine run cooler but not positive.

 

Did not check the gas mileage on the first tank but have not noticed any change in the gas mileage after that and am not at 4400 miles. The average after the first tank has been 18.4 mpg with higher amounts on straight highway driving at 65 & 70 mph. Am very pleased with the Ecoboost, 4x4 Supercab with the 3.55 gearing.

 

IMO,It seems to me 50 degrees and lower temps the EcoBoost might stay richer on the fuel mixture.My truck the mileage and performance seem to drop with temps under 50 degrees.Above 50 the mileage seems better and my truck seems to run the best with warmer outside temps.I also think that maybe they have them run richer in the colder weather because of the turbo's.Cooler air usually wants more fuel IMO.

Later Mark.

 

I'd say I agree, but it's hard to judge when I'm usually in 4x4 when the temps are below 50.

I can attest to my MPG improving around the 4th month I owned mine. When I bought my 2005 Scab, the mechanic who walked me through the new features explained that the truck will learn driving habits, conditions, and the quirks of it's own engine to get the best performance possible. The more I drove it, the better mileage I'd get. I can assume this has only gotten better with the newer vehicles.

 

^^^ This. ^^^ These fellers nailed it.

This is another one of those urban legends/myths started by some uninformed dealer lackey and then parroted here as gospel (Hey - it's the Dealer reps right? It must be true, lol).

Much like dealer-generated misinformation concerning the latest-gen SP507/515's being tapered and or/welded. Nope and/or Nope.

 

Purty sure yer ol'outboards or IO's don't have any cats or O2's to bugger up by running real rich.


MGD

 

Ur right, No cats

 

Ya im sure there is something in there, along the lines they over fuel, but its probably so minor you won't notice the difference. On my Ecoboost I had over 3,000 miles on it towing, the first 3 days I owned it. Every truck is alittle different, you can have two identical trucks and there both going to get different mileage no matter what. 18mpg is pretty dang good for a truck if you ask me and probably is about average for a ecoboost from what ive seen, if you bought a truck you probably shouldn't be worried about the mileage, if you cared you that much should have gotten a different vehicle.

 

Thats the boost from the Eco.