Gas tips (got in an email)

[NCFronty]

TIPS ON PUMPING GAS (Good information) I don't know what you guys are

paying for gasoline.... but here in California we are also paying higher, up to
$3.50 per gallon. But my line of work is in petroleum for about 31 years now,
so here are some tricks to get more of your money's worth for every gallon.
Here at the Kinder Morgan Pipeline where I work in San Jose, CA we deliver
about 4 million gallons in a 24-hour period thru the pipeline. One day is
diesel the next day is jet fuel, and gasoline, regular and premium grades. We
have 34-storage tanks here with a total capacity of 16,800,000 gallons.
Only buy or fill up your car or truck in the early morning when the ground
temperature is still cold. Remember that all service stations have their
storage tanks buried below ground. The colder the ground the more dense the
gasoline, when it gets warmer gasoline expands, so buying in the afternoon or
in the evening....your gallon is not exactly a gallon. In the petroleum
business, the specific gravity and the temperature of the gasoline, diesel and
jet fuel, ethanol and other petroleum products plays an important role. A
1-degree rise in temperature is a big deal for this business. But the service
stations do not have temperature compensation at the pumps. When you're
filling up do not squeeze the trigger of the nozzle to a fast mode. If you look
you will see that the trigger has three (3) stages: low, middle, and high. In
slow mode; you should be pumping on low speed, thereby minimizing the vapors
that are created while you are pumping. All hoses at the pump have a vapor
return. If you are pumping on the fast rate, some of the liquid that goes to
your tank becomes vapor. Those vapors are being sucked up and back into the
underground storage tank so you're getting less worth for your money. One of
the most important tips is to fill up when your gas tank is HALF FULL. The
reason for this is, the more gas you have in your tank the less air occupying
its empty space. Gasoline evaporates faster than you can imagine. Gasoline
storage tanks have an internal floating roof. This roof serves as zero
clearance between the gas and the atmosphere, so it minimizes the evaporation.
Unlike service stations, here where I work, every truck that we load is
temperature compensated so that every gallon is actually the exact amount.
Another reminder, if there is a gasoline truck pumping into the storage tanks
when you stop to buy gas, DO NOT fill up--most likely the gasoline is being
stirred up as the gas is being delivered, and you might pick up some of the dirt
that normally settles on the bottom. Hope this will help you get the most
value for your money. DO SHARE THESE TIPS WITH OTHERS!

[ariasse]

Thanks man

[EB_05_NISMO]

It's too cold this time of year to pump gas slow. I already think the pumps are too slow to begin with.

[bungyfish]

Pretty sure this one has been debunked already.
Storage tanks under the ground are well below the frost line where temperature stays constant regardless of the time of day.
Pumping slower to avoid vapor issues may be true, but it is on such a small scale that I doubt it would be noticed.
I think a better way to conserve gas it is to bike more... and drive slower on the highway and avoid fast starts.
Just my 2 cents.
Thanks for sharing.

[CoastalDefender]

Having been in the Petroleum Business for almost a year now (Fuel Truck Driver and Deliver Driver) I can tell you this advice is not quite accurate, and is a bit misleading as the amounts of wasted "vapor" is so minimal, it's virtually inconsequential.

[MOBEEBO]

Yeah, I got the same email and talked with a friend who used to replace the tanks at gas stations. He called BS on it too.

[navara009]

i think all of this might be true but would be so minimal that you would ruin all your hardwork at the pump if you missed a turn and had to do a U turn somewhere or redlined it once or went 4wding or something

[hbstriker]

I am an electrician at ExxonMobil, and the chemies at the plant have called BS on most of this stuff. Whenever we look for extra HP's in our cars or whether a new gizmo could work, we go right to the labs and start asking questions. They always tell us to carpool or ride a bike

[ARCTICFRONTIER]

Saving fuel in our trucks is easy.......just turn off the ignition. Then walk to work....grin.

I think most of this is BS. I would be curious what the temperature change of the gasoline is between morning and afternoon. A couple degrees maybe since the gas is underground where the temp is very constant. The email is right that a liquid expands and contracts with a temp change. But not a signifigant change. Service stations would correct for the temp change if this was a big deal.

I do fill up at half a tank especially in colder seasons. But not for the reasons this email says. I do it because I think having a fuller tank helps minimize water condensation from the air in the tank into the gas. That could be BS too but who knows.....

[Dr Phat]

The vapor loss one is BS immedietly. Unless you like every mL of gas. The storage tank one is a good one depending how low the tank is sunk into the ground. But its pretty much always around 65*F after X amount of feet into the earth.