Speaking of gas...
I've not checked this out at snopes or anything but it makes sense to me...
Tips about gasoline fill-ups... From an employee for Kinder-Morgan Pipeline in San Jose, CA, who has been in the petroleum pipeline business for about 31 years. Kinder-Morgan delivers about 4
million gallons in a 24-hour period from the pipe line; one day it's diesel, the next day it's jet fuel and the next day its gasoline. Kinder-Morgan has 34 storage tanks here with a total capacity of 16,800,000 gallons. Here are some tricks to help you get your money's worth when you fill up your car, truck or SUV.
1. Fill up your car or truck in the morning when the temperature is still
cool. Remember that all service stations have their storage tanks buried
below ground; and the colder the ground, the denser the gasoline. When it
gets warmer gasoline expands, so if you're filling up in the afternoon or
in the evening, what should be a gallon is not exactly a gallon. In the
petroleum business, the specific gravity and te mperature of the fuel
(gasoline, diesel, jet fuel, ethanol and other petroleum products) are
significant. Every truckload that we load is temperature-compensated so
that the indicated gallon age is actually the amount pumped. A one-degree
rise in temperature is a big deal for businesses, but service stations
don't have temperature compensation at their pumps.
2. If a tanker truck is filling the station's tank at the time you want to
buy gas, do not fill up; most likely dirt and sludge in the tank is being
stirred up when gas is being delivered, and you might be transferring that
dirt from the bottom of their tank into your car's tank
3. Fill up when your gas tank is half-full (or half-empty), because the
more gas you have in your tank the less air there is and gasoline
evaporates rapidly, especially when it's warm. ( Gasoline storage tanks
have an internal floating 'roof' membrane to act as a barrier between the
gas and the atmosphere, thereby minimizing evaporation.)
4. If you look at the trigger you'll see that it has three delivery
settings: slow, medium and high. When you're filling up do not squeeze
the trigger of the nozzle to the high setting. You should be pumping at
the slow setting, thereby minimizing vapors created while you are pumping.
Hoses at the pump are corrugated; the corrugations act as a return path
for vapor recovery from gas that already has been metered. If you are
pumping at the high setting, the agitated gasoline contains more vapors,
which is being sucked back into the underground tank so you're getting
less gas for your money.
Hope this will help ease your 'pain at the pump'.