Gas pumping tips.

My friend Bong forwarded an email to me from his friend who knows gas and has some tips on getting every penny of your buck when it comes to pumping gas. I am not sure if this is accurate but here it goes.

"Only buy gas or fill up your car/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 of gas is not exactly a gallon. In the petroleum business, the specific gravity and the temperature of the gasoline play an important role. A one-degree rise in temperature is a big deal in this business but service stations do not have temperature compensation at the pumps.

When you are filling up do not squeeze the trigger of the nozzle to run in the fast mode. If you look you will see that the trigger has three stages: low, medium, and high. In slow mode you are pumping at a lower speed and 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 into your tank becomes vapor. Those vapors are being sucked back into the underground storage tank so you are actually getting less for your money.

One of the most important tips is to fill up when your tank is HALF FULL/HALF EMPTY. 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 to think about: 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 into the storage tank 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."