5.4L engine 20 miles to the gallon
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From: Burleson/Athens/Brownsboro, TX
I know this might be hard to believe but you'll get better gas mileage on the top half of the tank than you will on the bottom half. So if you fill up on a regular basis at the 1/2 tank reading as opposed to near empty you should see an increase in mpg.
Originally I was a skeptic when my 70 year old mother mentioned she was getting more mileage when the tank was kept on the full side. So I decided to check this out with an older car ('79 Pontiac) I had been testing and tuning for best overall 1/4 mile, driveability and mileage.
Car is setup with O2 sensor, TPS, MAP sensor and data logger. Anyway I've been doing this for a few years now and sure enough as the fuel level in the tank drops below the mid point the engine begins to run progressively richer as it gets closer to empty. I have no idea why this would happen.
I also tested this on my FX4 and sure enough my mileage (always calculated manually) is slightly better when I keep the gas tank more than 1/2 full.
Rediculous, right!
Aaaawe I'm just messing with you guys.
........NO I"M NOT!
Originally I was a skeptic when my 70 year old mother mentioned she was getting more mileage when the tank was kept on the full side. So I decided to check this out with an older car ('79 Pontiac) I had been testing and tuning for best overall 1/4 mile, driveability and mileage.
Car is setup with O2 sensor, TPS, MAP sensor and data logger. Anyway I've been doing this for a few years now and sure enough as the fuel level in the tank drops below the mid point the engine begins to run progressively richer as it gets closer to empty. I have no idea why this would happen.
I also tested this on my FX4 and sure enough my mileage (always calculated manually) is slightly better when I keep the gas tank more than 1/2 full.
Rediculous, right!
Aaaawe I'm just messing with you guys.
........NO I"M NOT!
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Jim
Jim
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From: DFW
I have maintained a spreadsheet of every fillup for the last 6 years and when I buy gas, I always fill it up. When I would top off the tank to get ready for a long trip, I would notice that I got substantially better mileage. I filled up at half a tank or less several times as a test and it was consistent. Never have heard a good explanation, but I agree, it is a fact.
Most vehicles the EVAP system only runs if the tank is between 1/4 and 3/4. So the top half you dont get it to run as much.
you would actually get the best mileage if you always kept it above 3/4 but you'd have to stop every couple days and top off
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From: Burleson/Athens/Brownsboro, TX
because of the on board vapor recovery system, or EVAP. It accumulates vapors and puts them into the engine to reduce overall vehicle emissions. But basically it dumps precious gas in the intake before its needed and it wastes it away.
Most vehicles the EVAP system only runs if the tank is between 1/4 and 3/4. So the top half you dont get it to run as much.
you would actually get the best mileage if you always kept it above 3/4 but you'd have to stop every couple days and top off
Most vehicles the EVAP system only runs if the tank is between 1/4 and 3/4. So the top half you dont get it to run as much.
you would actually get the best mileage if you always kept it above 3/4 but you'd have to stop every couple days and top off
As much as I drive, I don't bother with filling up at a half tank, but it is interesting to know about it.
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Jim
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From: DFW
its better for fuel pump longevity to have more then half a tank as well, the weight of the fuel above will help the pump out, instead of trying to suck off the bottom. The fuel also helps keep the pump cool in warmer weather, and extended use.
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From: Burleson/Athens/Brownsboro, TX
Picked up the new truck August 5th and I have 9975 miles on her this morning. So pretty close to the same as you.
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Jim
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keepin her full
Well you find out most interesting things regarding your vehicle here. I'm going to try keeping the tank full as much as possible for a few months.
Say has gas gone down a bunch in the uSA in the last couple of months? We are down to 99 cents a liter, hasn't been this low in a few years. FS
Say has gas gone down a bunch in the uSA in the last couple of months? We are down to 99 cents a liter, hasn't been this low in a few years. FS
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From: Holt, MO
My 2010 has 62K on it in 15 months. I get 17.5 on two lane roads at 65 mph. If I baby it, I can get 20 to 21.
on the Interstate going 80, I get 15.5 mpg.
3.55 gears 5.4 super crew. running straight 87 octane.
Not sure how people are consistantly getting 20 mpg at 80mph with this truck.
on the Interstate going 80, I get 15.5 mpg.
3.55 gears 5.4 super crew. running straight 87 octane.
Not sure how people are consistantly getting 20 mpg at 80mph with this truck.
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Fasteel,
You probably know this but I'll mention it incase that the milage will suck from now till the spring no matter what we do, shy of just parking it for the next 5 months. An internal combustion gas engine needs more fuel to run properly during this time because of the cold, dense air quality we experience in the northern states and Canada.
So you may not notice an improvement in milage until the spring.
You probably know this but I'll mention it incase that the milage will suck from now till the spring no matter what we do, shy of just parking it for the next 5 months. An internal combustion gas engine needs more fuel to run properly during this time because of the cold, dense air quality we experience in the northern states and Canada.
So you may not notice an improvement in milage until the spring.
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From: DFW
Its a little lower, but we've dropped from 3.30 a gallon to around 3.00 mark
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From: White Lake, MI
Just like those damn Taco Bell lobbyists trying to push Methane as a renewable resource.
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Fasteel,
You probably know this but I'll mention it incase that the milage will suck from now till the spring no matter what we do, shy of just parking it for the next 5 months. An internal combustion gas engine needs more fuel to run properly during this time because of the cold, dense air quality we experience in the northern states and Canada.
So you may not notice an improvement in milage until the spring.
You probably know this but I'll mention it incase that the milage will suck from now till the spring no matter what we do, shy of just parking it for the next 5 months. An internal combustion gas engine needs more fuel to run properly during this time because of the cold, dense air quality we experience in the northern states and Canada.
So you may not notice an improvement in milage until the spring.
What I know about engines and how they work, you could put in a Thimble and throw over board!!
But I love coming here and reading about what all of you experienced fellows know about stuff.