MPG computer lies - badly!

[SpeedyV]

I have the quad cab with 3.92 gear.

Yeah, that doesn't help me. See my signature (crew cab, 3.92, all options). My payload sticker is the lowest on this forum, to my knowledge, per the list compiled by @devildodge.

 

[ddharris]

My 2012 Titan was getting about 10

Yeah, that doesn't help me. See my signature (crew cab, 3.92, all options). My payload sticker is the lowest on this forum, to my knowledge, per the list compiled by @devildodge.

ill see what I find . Be in the truck shortly.

 

[GRAYWOLF]

My entire history, except my first fill up (row 1 was baseline data for when I took posession)

Made a roadtrip to Jackson TN in March...the 476 trip was from Greenville TX to Memphis.

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[Jus Cruisin]

That's why it's been called Lie-O-Meter for years. Now with Ford, you can get into a each mode on the dash readout and actually set the calibration factor to actually get it close. Me? I don't check Meg much. I'll look at the mpg readout just because I use one of my tripodometers to track miles between oil changes and I have to scroll past it. The economy is what it is regardless if I calculate it or not.

 

[StuartV]

If this was directed at me, I have neither.
The issue in my case, is that my commute is less than a mile ea way, which has killed my MPG in every vehicle I've owned. Doesn't bother me. The upside is that I fill up every three weeks or so.

Cheers,

Thanks for posting that. I'm glad to see it's not just me and it's not just the 3.92 gears.

I work from home and everywhere I go on a semi-regular basis is within a mile or two. So, I was expecting my "city" driving to be low. But, I was not expecting my highway ride home yesterday to be so low. However, I'll give it the benefit of the doubt for now. I had it on Adaptive Cruise Control and the traffic was fairly heavy (typical Sunday afternoon on I-95 headed towards DC) so there was fair bit of slowing down and speeding back up. I'll hope for much better when the truck has another couple of thousand miles on it and I am able to do a road trip where I can use regular cruise control and just let it roll.

But I'm still disappointed that the onboard computer is so far off. Especially when so many of you are saying it's consistently within 0.5 (or better). Being off by 2.5 MPG just seems like a LOT.

 

[StuartV]

My entire history, except my first fill up (row 1 was baseline data for when I took posession)

Made a roadtrip to Jackson TN in March...the 476 trip was from Greenville TX to Memphis.

Sent from my SM-G965U using Tapatalk

You give me hope! We're getting about the same mileage for around town. I HOPE I can hit over 20 MPG at some point. My old truck certainly never managed that.

How fast were you driving on that trip from TX to TN?

 

[GRAYWOLF]

You give me hope! We're getting about the same mileage for around town. I HOPE I can hit over 20 MPG at some point. My old truck certainly never managed that.

How fast were you driving on that trip from TX to TN?

Limit+9...I think the limit in AR is 70, so 79...(84 in TX).

This pic was as I hit Memphis...I think it is a small decent from LR to the Mississippi

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[GRAYWOLF]

Also...3.21 2wd

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[sergetexan]

3.21 seems to be the common link to better MPG’s with this 8 speed. I enjoy my 3.92 and have had some good mpg on 200-300 mile trips (19-20), but around town 14-15 is best I expect to see, also 2 WD. Country roads or 60-65 does good, but once u are in 70-80’s drops back down.

 

[Willwork4truck]

I guess I will have to “break down” and manually calculate a couple trips to check.

I did purchase a rather heavy Limited 4x4, but I countered that with 3.21’s. I think theres a variance between trucks (gears and weight), computers and of course drivers but the latter is the highest.

On the same highway trip, my son, having almost the identical truck, (just less the pano), gets 2-3 mpg less on a consistent basis. But then he drives not only harder but 5-9 mph faster (often 79 in 70 while I go 70).

 

[StuartV]

Limit+9...I think the limit in AR is 70, so 79...(84 in TX).

This pic was as I hit Memphis...I think it is a small decent from LR to the Mississippi

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Okay... well.... Oh, well.... With 4WD and 3.92, I guess I'll never get the mileage you do. But, maybe I can hope for 17 - 18. At least on trips where the speed limit is not 70+. I am also a +10 driver on the speeds.

 

[Rob5589]

There are many variables in play. For one, if you want to get real picky, stick to one gas station for consistency; make sure your tires are properly inflated; double check your speedometer against a GPS device.

Fwiw, mine showed "current mpg" at 99 this morning while coasting through a bend in the road

 

[AbitaPro]

I haven’t checked the dash MPG, it is what it is. I simply add fuel when necessary.

There are so many variables that go in to maximizing fuel economy, it can become exhausting.

In the 70’s they lowered the Country’s speed limit to 55MPH, to increase fuel economy in vehicles do to the oil embargo and shortages. Everyone got better fuel economy, except we couldn’t read it on the dash.

But y’all have my interest, so at my next fill-up I will hand calculate, just to check.

 

[SpeedyV]

I simply add fuel when necessary.

Hard to argue with that logic

 

[J-Cooz]

With only 1,000iles on the truck you can't expect it to be good yet. I have just over 2000km on mine and it is getting better. The truck still feels really tight though and needs to break in more.

 

[silver billet]

I haven’t checked the dash MPG, it is what it is. I simply add fuel when necessary.

There are so many variables that go in to maximizing fuel economy, it can become exhausting.

In the 70’s they lowered the Country’s speed limit to 55MPH, to increase fuel economy in vehicles do to the oil embargo and shortages. Everyone got better fuel economy, except we couldn’t read it on the dash.

But y’all have my interest, so at my next fill-up I will hand calculate, just to check.

Well when you're dumping $100 of fuel into your truck every week/week-and-a-half, maximizing mpg becomes less about "exhausting" and more about "how do I do it?". And I can already hear some others here thinking "you don't buy a truck and expect to get good mpg", which is true, I don't "expect" it, but I "want" it none-the-less. I bought the truck to do trucky things, like tow a travel trailer, doesn't mean I'm suddenly not interested in mpg just because I have a travel trailer that needs to be tugged around.

For myself, I can't complain really. Computer says 24+ mpg, so even dropping that down by 3 to 4 mpg if the computer is off, means I'm still probably hitting the rated MPG.

 

[brotharon]

Well, the only reason that I care is that I am really into numbers and I like keeping track of things like cost of ownership of my vehicles and long term fuel economy. I suppose I could make a case that if I noticed the fuel economy drop off significantly from where it is presently that it could indicate something needing repaired, but that isnt the real reason. I just like numbers a lot and want to see them.

 

[Lize]

Is there a chance you have got imperial mpg selected in the settings?

I only ask as the figures in your original post looked familiar to my ballpark in head UK conversion. When double checking 17.2 in UK mpg is 14.3 US mpg and 14.5 is 12 US.

As an aside, I was really impressed that I could select the imperial mpg option and don’t have to do a conversion. Never seen this before only km or miles.

 

[TruckDriver]

One thing I hadn't seen mentioned is calibration (if any) of the EVIC readings - one way I could see that my EVIC ratings weren't calibrated was a few days ago when I had been driving with the fuel light on for a while

What I noticed is the range countdown was 1:1 for a few miles and then would basically pause until it seemingly recalc'd the range based on my foot and the fuel in the tank... now a mile or two is one thing, but my range was '15mi remaining' for ~20mi before it continued to count down again....

So as suggested above - fill up a gas can and run that truck dry (or damn near) perhaps and maybe the EVIC would recognize its bottom end?

(or am I just crazy?)

Also for thread reference; 3.92 gears and aCar reports 14.101mpg with a lifetime max of 15.660 over ~8300mi / 34 Fuel ups / 616gal used

 

[DraKhen99]

Well, the only reason that I care is that I am really into numbers and I like keeping track of things like cost of ownership of my vehicles and long term fuel economy. I suppose I could make a case that if I noticed the fuel economy drop off significantly from where it is presently that it could indicate something needing repaired, but that isnt the real reason. I just like numbers a lot and want to see them.

Yes, all of this! I too keep track of my cost of ownership, and thus fuel economy.

I try to maximize whatever I'm driving, or at least see if I can match the EPA ratings... which of course, anyone with a heavy/crew cab/3.92 truck probably won't. The only one which got close was my 2011 F-150, which was an extended cab, 3.55 gears, and was a Lariat, so upper-middle trim level. It got 16.5 (EPA rated it at 15/21/17 cty/hwy/comb.) I did mostly city driving with that truck. Curiously, it did better than my 2015 F-150 (same engine/drive/gears) which was a crew cab and a loaded up Lariat. It only got 16.15, and I drove mostly highway.

-John