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Old 01-25-2012, 03:49 PM   #11 (permalink)
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Escape #2 - '13 Ford Escape Titanium

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You also need to remember that if you live in the USA (except for Hawaii), gas pumps don't compensate for temperature. 1 gallon of gas at 60 F weighs 2% more than 1 gallon of gas at 90 F. So using 6 lbs / gal, a vehicle with a 36 gallon gas tank will have 216 pounds of fuel on at 60 F. At 90 F, the same vehicle will only have 212 pounds. In an area with extreme temperatures, there might be a 100 degree swing from the winter to summer. For example, it gets down to -27 F here almost every winter and gets up to 85 F every summer. If that same 36 gallon gas tank was filled at -27 F, it will weigh 228 pounds.

So, on the coldest day of winter a large pickup truck could be carrying 228 pounds of fuel on a full tank, and on the hottest day of summer the same truck would be carrying 212 pounds of fuel.

I used the largest non-commercial gas tank I could think of, obviously it affects smaller tanks less.

Canadian and Hawaiian gas pumps do compensate for temperature, so always filling with the same amount would work there.

I got the "1% per 15 degrees" from this site -
Turn Down Hot Fuel

Last edited by p38fln; 01-25-2012 at 03:50 PM.. Reason: 30/15 is 2 not 4
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