Fuel Mileage Reading Off?

[Expedition Dave]

Any others check their fuel meter variances? I am getting a 5-6% favorable discrepancy all the time when measured with a calculator miles vs gallons filled.

And please, before you say "all factory readings are off--!" I can tell you other vehicles I have owned were w/i normal variations of pumps and temps of +/- 1-2%).

I always measure after 3 clicks, and on level ground. If you check your numbers, please try to do it over several days and gas stations, like I have b/c I noticed it to be this way over multiple fuel station pumps, and over 13K in miles.

OMMV

 

[Xeniselamya]

Everyone loves to check, for example, after some refueling (I will not name them), the consumption increases with the same mode of use, of course I no longer refuel there!

 

[ZR600MN]

The fuel mileage on my 18 shows almost 1 mpg better than if you check it manually.

 

[Saltwater Soul]

My '18 is also almost exactly 1 mpg optimistic compared to my hand calculated numbers. This is over the last 30 fuel ups.

 

[aggiegrad05]

There’s another thread on this somewhere but, yes, it seems that everyone who’s checked come to about 1mpg optimistic on the dash.

 

[DWs-TTEB]

Speaking of MPG, I fabricated spreader spring clips (highlighted green below) to my front disc brake pads (new pads) last Friday. This gained me 3 more MPG. Don't know why Ford stopped putting these in the newer F150s/Expys. If you research brake hardware by model the MY2005 F150 was the last year the pads have the holes to receive the spreader spring clips. I just drilled the required holes in the pad liner (behind the pad media) while having the pads on the rotor slides with a joint clamp holding them together (leave the clamp on the top while installing the caliber). I also researched the front calibers for the MY18-20 expys & yes they can receive these spring clips w/o issue. I have already driven 370 miles with them on mine (no issues). YMMV!


https://www.autozone.com/brakes-and...last-brake-disc-hardware-kit-h5795q/78220_0_0

example:

 

[mwl001]

There’s another thread on this somewhere but, yes, it seems that everyone who’s checked come to about 1mpg optimistic on the dash.

See here. I'm pretty sure it's the same procedure as on my 5th Gen Explorer as well, fixed mine and now seems to be within 0.5mpg or better. Once you've calculated the ratio of used gas to calculated you adjust it in the menu.
https://www.expeditionforum.com/threads/3-000-mile-report-through-the-north-east.46647/#post-427907

 

[5280tunage]

Speaking of MPG, I fabricated spreader spring clips (highlighted green below) to my front disc brake pads (new pads) last Friday. This gained me 3 more MPG. Don't know why Ford stopped putting these in the newer F150s/Expys. If you research brake hardware by model the MY2005 F150 was the last year the pads have the holes to receive the spreader spring clips. I just drilled the required holes in the pad liner (behind the pad media) while having the pads on the rotor slides with a joint clamp holding them together (leave the clamp on the top while installing the caliber). I also researched the front calibers for the MY18-20 expys & yes they can receive these spring clips w/o issue. I have already driven 370 miles with them on mine (no issues). YMMV!

View attachment 40484
https://www.autozone.com/brakes-and...last-brake-disc-hardware-kit-h5795q/78220_0_0

example:

View attachment 40485

Funny, I noticed these on my wife's Acura when replacing her brakes a month or two ago. So effectively you created your own. Nice idea.

 

[DWs-TTEB]

Speaking of MPG, I fabricated spreader spring clips (highlighted green below) to my front disc brake pads (new pads) last Friday. This gained me 3 more MPG. Don't know why Ford stopped putting these in the newer F150s/Expys. If you research brake hardware by model the MY2005 F150 was the last year the pads have the holes to receive the spreader spring clips. I just drilled the required holes in the pad liner (behind the pad media) while having the pads on the rotor slides with a joint clamp holding them together (leave the clamp on the top while installing the caliber). I also researched the front calibers for the MY18-20 expys & yes they can receive these spring clips w/o issue. I have already driven 370 miles with them on mine (no issues). YMMV!

View attachment 40484
https://www.autozone.com/brakes-and...last-brake-disc-hardware-kit-h5795q/78220_0_0

example:

View attachment 40485

*Clarification:

So, Dec 11, 2020 I put new rotors and pads on all 4 corners. After a few weeks and car washes I noticed the front passenger-side wheel was x5 as dirty with brake dust then the other wheels. I diagnosed this as a stuck caliber. Got a new caliber, flushed the brake fluid and greased everything. I then got a whole new wheel n tire package put on. But I still was having the extreme amount of brake dust on that same tire and it was extremely hot, just being within a foot of the wheel you could feel the heat on your face. So now I’m concerned as hell. I buy new front ceramic pads vice the semi-metallic I had on and the hardware I mentioned. Post all this, the inner pad was seizing/stuck against the rotor.

Greasing the slides the pads sat on temporary gave me 3+ MPG. Once that grease got hot and dust got in there it would seize again. When I put the 2nd pair of pads on, I found the stuck inner pad and it was so worn down it would have had no pad media by March. The pad tabs (that sit in the slides) were just a little bit longer than what it should have been causing the extra friction. So now, I have a solid +3-4 MPG added with the spreader spring clips installed as insurance this won’t happen again.

My new tires are heavy and that sucked up 3MPG. My city is now 16-17, hwy 22-24. Minus the stuck brake pad constantly against the rotor in addition with the spreader springs & watching my MPG gauge is how I came up with 3-4+ MPG. HWY speeds for me = 70-80 MPH, city = 35-45 MPH. My fuel economy is uncorrected as well. Having my 5-Star 93 Performance tune loaded & the heavy tires is also costing me MPG. I will load the Daily/Street 93 5-Star tune & see how that goes. Next road trip I will put the stock wheels/tires on to see how much that adds.

 

[5280tunage]

Good Lord, is yours not under warranty still? Seems like a stuck caliper piston should have been warranty-able. They might have required factory stupid pads to prove it wasn't the issue. But still. Calipers aren't cheap (well maybe made anyways).

 

[Expedition Dave]

Kudos to user WAKEBOARDER for providing this link:

https://www.f150forum.com/f118/fix-inaccurate-mpg-display-2-minutes-421912/#post5852007

Did the mileage correction in the "Engineering Menu". TOoo easy and there is a host of other interesting things in that menu that I have no idea what the do.
PRO-TIP: Don't scroll down, scroll reverse or else it is the last thing that pops up. I will leave it to the big(ger) Ford brains here to see if anything else in that menu has value.

I entered the value "935" so we will see after a couple fill ups where my mileage is.

 

[DWs-TTEB]

@Expedition Dave

 

[wakeboarder]

Kudos to user WAKEBOARDER for providing this link:

https://www.f150forum.com/f118/fix-inaccurate-mpg-display-2-minutes-421912/#post5852007

Did the mileage correction in the "Engineering Menu". TOoo easy and there is a host of other interesting things in that menu that I have no idea what the do.
PRO-TIP: Don't scroll down, scroll reverse or else it is the last thing that pops up. I will leave it to the big(ger) Ford brains here to see if anything else in that menu has value.

I entered the value "935" so we will see after a couple fill ups where my mileage is.

Your welcome. The real kudos should go to the guys on the F150 forum.

If I have an issue, I usually search the F150 forums as well because there are a lot of similarities.

 

[Expedition Dave]

My mileage utilizing "935", over 3100 miles (99% highway and 8 fill-ups) measured to be a bit off of the actual readings (meaning my actual calculated mileage is better than the trip computer shows).

Five out of eight fill-ups (two were near equal, and 1 was .22 of an MPG less) were this way. While this is a good safety margin for error, I'd like it a bit closer so will raise it to "940" to satisfy my inner mad scientist/child who can't leave well enough alone...