Real World Gas Mileage Math?

broncobuster2550

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An additional source of noise is the different pumps you go to may have a slightly different shut-off tolerance for what it thinks is "full", which is influenced by flow rate and general cleanliness/maintenance of the venturi tube. One pump may end up putting slightly more fuel into the tank than another before it clicks off.

Also note that on Ford capless fuel you should not "top off", first click is good (unless the pump obviously clicked off early).
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DakotaTimber

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I have found that though they may be close , they are never 100% correct , they are just a guide to go by . By all means use the Odometer & do the math when you fill up , its still would not be 100% correct for a couple of reasons , one being Fuel expansion in the Tank with ambient Temp. from one fill to the next , then you have the meter on the Pump , is it calibrated , then it would be driving habits , altitude , on & on ,its just a guide , as with the gal. till empty , I wouldn't bet my life on it .
In other words for the best mileage always fill in the coldest spot you can find at the coldest portion of the day. That's why rural fuel deliveries always occur in the middle of the afternoon.
 

IronMikeGolf

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We are leaving for our longest driving trip in several years in two days. NE Ohio to Wilmington, NC and then Myrtle Beach, SC for 10 days.

Going to do hand calculated MPG using 89 octane fuel. Starting off with 6 gal of 83 octane in the tank. Back Apr 3.

I've been getting 31 MPG and change on highway driving on 83 octane. Dunno if we are still on winter blend here. All short trips here so far.
 

wiyeti

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Thought I’d share last four tanks drank by my OB, 87 octane, 60/40 mix of highway/city. Normal mode. Better mileage was warmer, temps were in 40s to 50s. Dash pretty consistently showed 2mpg better. Generally the same as my CX-5 the Bronc replaced so pretty happy.
Ford Bronco Sport Real World Gas Mileage Math? 524C7A3B-E323-4C94-863D-7C4EFC602404
 

BagOJuice

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I’m currently at 26.2 mpg total for my badlands. ~2k miles in. Although I did just put some Discoverer at3 4s tires on so I’m curious the impact this will have on my mpg avg. small sample but around 100 miles on the new tires I don’t notice much, even had a 31mpg half hour trip on them the other night. So far, pretty pleased with this especially with the bigger 2L engine
 
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Osco

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Warmer weather now. Been running 89 octane for several hundred miles now.
I may have to eat my own words.
On regular in the winter, 30's to 50's, 26.2 mpg long term avg on the dash info.
Now on 89 and a bit warmer, 40's to 70's, my new avg mpg is 27.0.
Ok so the summer fuel mix has more energy. Lots of testing left right !
I swear my little 1.5L feels smoother on 89 octane...
BUT I'm at 3200 miles now and still think my engine is STILL breaking in..
Boy all of this info was typical internet useless right ! :'P
 

SLJ

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In other words for the best mileage always fill in the coldest spot you can find at the coldest portion of the day. That's why rural fuel deliveries always occur in the middle of the afternoon.
Storage tanks are typically underground so there is little difference in fuel temps no matter when you fill up.
 

Cabezone

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So if the sport is anything like my Cherokee when it's below 45 degrees it will put power to all four tires while on the highway. So your MPG is going to take a hit in cold weather because of it.
 

RSH

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I don't quite have 1000 miles on my Badlands yet, but the only way for me to match the EPA hwy mileage rating is driving on flat mostly open hwy in ECO mode @ 65/75 mph. I didn't buy it for fuel mileage, and considering it weighs in the 4000lb range when loaded and has the aerodynamics of a brick it does ok.
 
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DMEARC

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An additional source of noise is the different pumps you go to may have a slightly different shut-off tolerance for what it thinks is "full", which is influenced by flow rate and general cleanliness/maintenance of the venturi tube. One pump may end up putting slightly more fuel into the tank than another before it clicks off.
I agree. The difference in pumps, plus the tolerance range of the fuel flow meter in the BS is more than likely the cause of the variation people are seeing between the vehicle calculated MPG vs manually calculated.
I view car fuel flow meters the same way I view aircraft fuel flow meters: a nice-to-know estimate, but nothing I’m going to bet my life on!?
 


Kachadurian

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My F-150,
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All the same,
Dashboard mpg reads about 8 to 10%
More than the accurate/actual math of miles divided by gallons to the tenth.
Was the same with my two Tacoma's.
No big deal to me, I like seeing 26.1 vs 24 mpg on the screen.
Unless you were at the same pump in exactly the same place, and the valve stops at exactly the same place, you really have no way of knowing for sure that you have put the same amount of gas into the car from fill up to fill up. How do you control for that?

That said, odometer over a series of fill ups for about 100 gallons is probably the most accurate.
 

Osco

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Unless you were at the same pump in exactly the same place, and the valve stops at exactly the same place, you really have no way of knowing for sure that you have put the same amount of gas into the car from fill up to fill up. How do you control for that?

That said, odometer over a series of fill ups for about 100 gallons is probably the most accurate.
Its not that critical. My math was always an average over a week's worth of driving and for me that was an average of 2,000 miles per WEEK. But I did fill up five or six mornings a week at 3 am at the same station and mostly at the same pump always feeling the same pump pressures. If that matters to you.
I did many weeks, due to boredom at the wheel I had lots of time to play with various methods of reaching for max mpg's.
That amount and frequency of testing would produce good reliable data and it would cover the ounces of difference in fill up amounts easily.
Was a professional driver for decades. Logged 3.2 million miles on driver's log books. You'll just have to trust the fact I am speaking from experience. Or defend your position as you see fit.
And that is " How I control for that" as you say. :'P
Quid pro quo, balls in your court. I look forward to a good constructive debate brother...
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