Am I crazy? MPG on “Crap gas”

[Ruger]

For a same type of driving on the same way/road, the factor that can influence a lot MPG is wind , morever with high truck . But, may you have consider this data also...

Absolutely true! On an I-80 trip to Incline Village, NV in March of this year I was bucking a 30 mph headwind and got 13 mpg with my GEN1. Three weeks later on the same trip, same route, same cruise control setting, same load, and same fuel (Sinclair midgrade bought at the same station) I got 14.5 mpg when the wind was negligible.

Wind, fuel formula (winter gas has about 5% less energy by volume than summer gas), fuel quality, tire everything (pressure, design, condition, etc.), load, driving habits, all of the factors under the hood (air filter condition, oil, etc.), and even air temperature play a role in MPG. To truly test if fuel quality is affecting fuel economy it would require a vehicle that was completely serviced and inspected before the first run and before the second run, a pair of track runs, and identical meteorological conditions for the two runs. And as @MDJAK sagely points out, I think it would take a far better on-board fuel computer than what Ford installs in Dearborn. It'd be fun to do, but most of us can't manage the necessary scientific rigor.

 

[Keith88]

Absolutely true! On an I-80 trip to Incline Village, NV in March of this year I was bucking a 30 mph headwind and got 13 mpg with my GEN1. Three weeks later on the same trip, same route, same cruise control setting, same load, and same fuel (Sinclair midgrade bought at the same station) I got 14.5 mpg when the wind was negligible.

Wind, fuel formula (winter gas has about 5% less energy by volume than summer gas), fuel quality, tire everything (pressure, design, condition, etc.), load, driving habits, all of the factors under the hood (air filter condition, oil, etc.), and even air temperature play a role in MPG. To truly test if fuel quality is affecting fuel economy it would require a vehicle that was completely serviced and inspected before the first run and before the second run, a pair of track runs, and identical meteorological conditions for the two runs. And as @MDJAK sagely points out, I think it would take a far better on-board fuel computer than what Ford installs in Dearborn. It'd be fun to do, but most of us can't manage the necessary scientific rigor.

Youre making me want to engineer the hell out of this.

 

[DaveInMn]

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I always fill mine with top-tier 91 non-corn gas. My normal driving (mostly rural, little city), hand calculated gets me 19.4-20.1. I reset Trip 1 every time I refill and its usually off by .2-.5. I've never reset Trip 2 and at close to 11k miles, its at 19.2 mpg.

I'll see what 2025 brings, but so far, this one's a keeper.....
.

 

[smurfslayer]

keep in mind, you’re probably getting better efficiency now in warmer temps with summer blend fuel

Also, moving around a 4 wheeled 3 ton brick is hard. At 60mph, I’ve pulled 19-20mpg, and it goes down from there. I avereaged 17 on tires at 37/36 on my move, and I think my average speed was about 62-ish on the last leg - lots of I10, this included a stretch east of Houston where the average ‘customary’ speed seemed to be 95. I know this because everyone was doing more than 85 and a cop of some sort passed several right lane drivers doing 90 at about 95-100. I was in the right lane when he passed us. And obviously some traffic going through Houston, etc.

 

[Madhouse]

gas mileage isn't something I look at too much in this truck, I don't expect it to be anything to brag about

and it doesn't disappoint - I use 93 only and can't really get much better than 14 mpg anywhere

then again, I absolutely do not feather the pedal, why buy 450hp if you're not gonna use 450hp

 

[Ruger]

gas mileage isn't something I look at too much in this truck, I don't expect it to be anything to brag about

and it doesn't disappoint - I use 93 only and can't really get much better than 14 mpg anywhere

then again, I absolutely do not feather the pedal, why buy 450hp if you're not gonna use 450hp

Oh, me either! If you buy a 6,000 pound vehicle with lots of suspension travel and a 400 bhp engine and expect to brag about fuel economy you're just fooling yourself. I actually get 16 to 16.5 mpg in town on midgrade gas, but at 75 to 80 mph it's a different story. I'm happy with that. My GEN1 is the finest vehicle I've ever owned, and I bought it for performance rather than economy. If I want economy there's my wife's Toyota Venza hybrid - a reliable 40 mpg.

 

[CruiserClass]

I’ve done this multiple times with the same result. Same exact route driven. Same time of year. In cruise control. Idc but… am I loosing my mind?

Two things can be true...you could both be losing your mind and getting better gas mileage for some reason. It is possible that whatever your equivalent of State Weights & Measures hasn't certified the other station correctly and the pumps are cheating you? Temperature difference when dispensed? Ethanol content? All could effect the amount of energy in a given gallon. Seems like a big swing to account for on those factors, though.

Do you guys do the summer gas/winter gas thing where it's a different formula for part of the year, and is there any correlation there? I lose about 2 mpg with winter gas.

 

[WisestIowan]

Fuel stations have contracts with jobbers where they have to buy the branded fuel of the station regardless of price. An unbranded station is still buying one of 5 or 6 brands of fuel they just don’t have a jibber agreement where they have to buy a specific brand. Typically they buy whatever is cheapest but it’s still Shell/Chevron/BP/Velero/etc fuel.

I can talk gas station operating all day. I work in commercial real estate debt and have several Gas Station/C-Sotre clients. Pre-COVID unbranded made around $0.04-$0.06 more per gallon due to the ability to buy whatever is cheapest. Post-COVID they’re gaining around $0.12 per gallon for the same quality fuel.

Don’t be scared to go to an unbranded station. It’s still the same fuel you get at branded stations. All grocery/costco/sams/buccees/etc are all unbranded but you don’t think of them like that.

 

[GordoJay]

I don't know if blending has improved, but it used to be that "10% ethanol" gas was anything between 1% and 25%. Ethanol produces less energy per gallon when you burn it, so mileage drops with ethanol content.

 

[MDJAK]

gas mileage isn't something I look at too much in this truck, I don't expect it to be anything to brag about

and it doesn't disappoint - I use 93 only and can't really get much better than 14 mpg anywhere

then again, I absolutely do not feather the pedal, why buy 450hp if you're not gonna use 450hp

Agree. Though I do look at the price of gas, when you need to fill, you need to fill. I was close to empty recently and not near Costco where I get gas 90 percent of the time. I filled at a Valero where it had come down from 4.99 to 4.79 to now 4.59. 21 gallons cost me $100, pump cut off, and I didn't bother restarting. Gave me about 3/4. Yesterday Costco was $3.79. My math is weak and I'm not taking out my old Texas Instruments calculator (nor my iphone) but I figure that fill at Valero cost me and extra 16 bucks which does not break me but surely doesn't please me.