Well folks, I'm more confused and frustrated now than ever. The truck is totally back to stock, with the exception of the topper. You can read the results of the "test drive" after getting it out of the shop with the PCM update WITH the mud flaps in place in the first post.
This time, WITHOUT the mud flaps, I took it on the same route, same speed, with no wind....the away trip came out at 14.8mpg, and the return trip was 18.1mpg. I think the only reason it reached the 18 mark was because the last 2 miles on the return trip was a slight downhill, and the speed limit is 65mph.
The reason I am so frustrated is because there is just no consistency with this truck. Every time I drive the same route/speed, the results come out differently....sometimes they are close, and other times there's a huge gap. Also, when I pull those lower 13-15mpg numbers, they are not that much off of what my old 1977 F150, with a 400 and C6 4 speed gets.

I checked my trip odometer B, that was reset when I changed the oil at 2900 miles....since then I've put 1575 miles on the truck, with the MPG averaging 16.2.
I suppose I should be happy that the electronics are behaving now, and the tranny is shifting better, but it looks like this truck will never reach that magic 20mpg mark that many have/are reporting.
I've even considered selling the high rise topper and buying a cab height model, but I suspect that would be just spending more money with minimal return. OK, I'll stop venting and leave it alone.

I suppose my only option is to just admit to myself that I bought into the hype and advertising, suck it up, and see what the next generation of F150s will bring.

 

Ed - you really need to calculate your MPG and average it over a bunch of tanks. There are way too many uncontrollable variables to rely on a short trip and the lie-o-meter.

Track your MPG over several tank fulls (Fuelly.com is one option - see my signature).

 

I have a 40 one way trip I take that is a pretty good test of fuel mileage. Only 3 stop signs, and usually light traffic. I have gotten as low as 18 mpg and as high as 24 mpg as indicated on the Scanguage.

I have done a 164 mile round trip driving the speed limit which is on a 2 lane with a max of 65 mph and got an easy 20 mpg average on several occasions.

Factors I have observed that make a huge difference in the overall avg for the day:

1. idle time. Stop at a stop sign and have to wait for a couple of minutes and you loose allot of mpg. Usually I can watch the "current" reading of the scanguage drop as much as 1 mpg while waiting for traiffic.

2. Pass one slower moving vehicle and you might as well throw in the towel. Like in the good old days, kick in the 4 barrel and watch the fuel gauge drop.

3. Wind. Even with all of the hard work that Ford has done to make these trucks more efficient against the wind, any head wind or an increase in speed will cost mpg.

4. Air conditioning, or running the compressor for defogging the windows. I see a drop of at least 1 mpg when I turn on the A/C. Everytime.

5. And of course "speed". My truck will drop from 20 mpg at 65 to 18-19 at 75 everytime. Hit 80 mph and above and I don't even look at the scanguage any more as I know it will drop to at best 17 mpg. Usually cruising at 83 mph for about a hundred miles it will show no more than 16 mpg.

Just some ideas to kick around when you are trying to get the best mileage out of these trucks. So many variables make it impossible to compare overall fuel mileage with so many different types of drivers and highway conditions.

I think the best method is to not worry about what others are doing, but look at what can be done to improve the mileage for your vehicle.

 

Out of curiousity, I went to Tirerack.com to get some stats for the tires Ed mentioned.
Most 275 65x18 tires are 32.1 inch diameter and 40 lbs.
275 70x18 tires are 33.1 inch diameter and a few pounds more. However, the E load range tires are more like 54 lbs.

The diameter difference is only 3%, which means, everything else being equal, you'd be getting about 1/2 mpg better then you'd calculate, as your milage driven would be 3% greater then the odometer, or trip computer would indicate. Not a real player. Ed said he put E load range tires on his truck; that may have been a 30% weight change, and would have to be tested to see if it makes a real difference

Also out of curiousity and based on this thread, I had a long talk yesterday with the service manager of a Ford dealership. In short, he said the Ecoboosts were running great, and posing few problem that he had seen. He said if you're happy with the way your truck is running, don't bother to have the ECM updated.

He pointed out that a few years ago, Ford was having problems with some diesels, so they put out a change that, among other changes, slightly derated the engine. Of course, some people were happy the way their truck was operating, but not pleased after getting this program upgrade.

He saidyou may get something good from an upgrade, or you may get a change you don't like. So, if it ain't broke, don't fix it.

He talked about how the computer senses "how you drive" and over a period of time, makes changes to adjust to your habits. I can't explain this any better, but he said that a new truck will make changes in transmission shift patterns based on how you drive.

Finally, he said he bought a new 2010 F-150 at the end of last year. He got $8500 in rebates alone, plus his employee discount, which I think is a little ways below invoice. So that buy was probably about $13,000 below sticker. Being the Ford dealer in Park City, UT which is at 7000 ft. he said the performance difference between his truck and an Ecoboost is very noticble, but he's very happy with what he's got.

 

Your right Charlie. That was my thought too, which is why I've not reset the Trip B since the truck's first oil change. In 1575 miles of driving since the oil change, the mpg average is 16.2.

I've just been trying to pin point the accessory that has caused the most damage to the MPG numbers. So far, everything is pointing to the Big-O tires I put on it, those cost me about 5 mpg, with the topper being second at about 2mpg. Looking back at all the numbers/accessory combos I've recorded, the grill guard causes less than a 1mpg loss, and the mud flaps don't seem to make a recordable difference.

My end goal is to routinely achieve 19-20 on the highway, which I don't think is too much to ask/expect considering the claims/advertising about this truck/engine.
Side stepping the issue of voiding the warranty, I'm thinking that the only way that is gona happen with my truck, is when/if somebody comes out with a tuner for the EB, and a QUALITY economy tune.

 

I still wouldn't trust the lie-o-meter. I know the 2011s are a lot closer than my 09, but good ol' fashioned miles/gas used is probably going to give you the best real MPG comparison. In fact, if at all possible, try to use the same pump or at least the same station (and gas).

I can tell you that my PHP economy 87 tune has increased my MPG by .82. But, and this is a BIG but, I was averaging 17.40 before I installed the tuner and I was doing a lot of towing before I installed it. So in reality, I'm probably only up .5 MPG.

 

I thought if people were worried about the difference between 16mpg and 20 they bought a car, maybe I was wrong.

 

I guess if your rich enough, you don't have to worry about the difference between 16 and 20 mpg....let's break it down

- 26 gallon tank @ 16mpg (26x16)=416 mile to a tank

-26 gallon tank @ 20mpg(26x20)=520 miles to a tank

That's a 104 mile difference per tank of fuel

Let's assume that gas is $3.80 per gallon....
$3.80x26=$98.80 to fill the tank

That means the difference between 16mpg and 20mpg is:
104/$3.80= $27.36 more for each tank of fuel between 16 and 20mpg.

Now let's figure it up on a 1,000 miles of driving, and look at the difference...
1,000/520=1.92 tanks of fuel
1,000/416=2.40 tanks of fuel

1.92x26=49.92 gallons of fuel
2.40x26=62.40 gallons of fuel

@16mpg: $3.80x49.92= $189.69 fuel costs
@20mpg: $3.80x62.40= $237.12 fuel cost

So for every 1,000 miles of driving at 16mpg versus 20mpg it costs an additional $47.43
Let's say that the lifespan of your truck will be 100,000 miles. The fuel cost difference over the life of the vehicle would be: $4,743.00, assuming that fuel remained at $3.80 per gallon.
So I would have to say yes, for me there is a difference between 16 and 20mpg.

My only point in this whole thing is that with an advertised rating of 21mpg highway, these trucks should be able to consistently pull 18+ when driven conservatively at 70mph. For me that just hasn't/isn't happening. That's only my opinion, but I don't think it's an unrealistic expectation.

Geez.....I went and turned this thing into another MPG thread! Sorry folks. Let's get back to the original thread title.......
The tranny on my truck is doing much better since the update. I agree that if it's not broke, don't fix it.....but having mine updated made a very noticeable difference.

 

The advertised 21 MPG is for a 2WD with the fuel saver package IIRC.

 

Not trying to be a butthead, but actually the 2wd version with the EB says 22 highway on the sticker. The sticker on my truck (4x4) shows 21 highway, with the small print beneath it saying that most drivers will see 17-25mpg.

 

Tires do make a huge difference. I finally learned that many years ago when I bought a new set of Bridgestone tires for my wifes Explorer. I always go bigger on replacement tires and this time was no different. After making the sale and installing the tires the salesman says that you'll like those tires, but you'll lose about 2 mpg. Now I new I would lose a bit because of the larger tires. But darn if he was not right on. After figuring in the odometer difference, my fuel mileage was always about 2 mpg lower. It was the same for my 97 F150, 2000 and 2003 Expeditions, and my 2005 Supercrew. I always lost fuel mileage when I went up a size or two in tires size.

If fact on my 2005 supercrew I was at about 17.5 highway mileage in stock form. After putting on bigger tires, SI/DO exhaust, "Gotts" on the intake, and the EDGE tuner, I finally got the mileage back up to about 17.5 on the highway. Best it would do. And you have to remember that it was not to many years ago that we all had 15 inch tires on a half ton truck. Now the smallest is 17, with some up to 22 inch in stock form. Allot of additional rolling weight, and mass with bigger brakes as well.

So I think you are spot on to take a hard look at the tires.

Not sure about the bed cover. Just looking at it, I really don't see it having a negative affect on highway fuel mileage.

But at the end of the day, after dusting off the boots, it all comes down to what you need your truck for.

 

How many miles are on your motor? Maybe it's not fully broken in yet? I know I can never get the advertised fuel mileage because I am an aggressive driver with a lead foot. I know with an EcoBoost, man, turbos I would be sucking some gas.

 

Do you run on cruse control when testing ?? as the drive by wire makes it hard to maintain a steady speed and rpm.
Cruse will be more acurate.

 

I do run it on cruise when I'm doing a "test drive". Normally I will get on the highway, get the truck up to speed, then set the cruise and then reset the MPG dash gadget. I don't have to worry much about traffic here in north central Montana.....more so the wind and weather. I always try to make sure things are as similar as possible any time I take the truck out to test something, especially the mpg.

Whitebeast: I wasn't trying to be a butthead about the advertised MPG, so if it came off that way, I'm sorry. No offense intended. My truck currently has just over 4500 miles on the odometer.

 

After thinking about it, and cruising around a couple of other forums, I got an idea.....I checked the air pressure in the tires, and they were all dead on with the 35psi indicated on the door sticker.
I pumped 5 more psi into each tire, just to see what would happen (40psi) and took a drive over the previous route.....the truck pulled 19.8mpg@ 70mph......maybe there is substance to this "rolling resistance" thing.
Now I have to decide if I want to put up with the rougher ride and wear out the center tread on the tires versus the extra mpg.......decisions, decisions. As badly as I've become obsessed with getting 20 out of this truck, I think I'll drive it with 40psi in the tires for a while and just see how it goes.