Fill your tank in the morning

There are some misleading facts on how to save on gasoline.

You may have heard that it's best to fill your gas tank in the early morning while the fuel is cold. The theory goes that fluids are more dense at lower temperatures, so a gallon of cold gas actually has more gas molecules than a gallon of warmer gas.

But the temperature of the gasoline as it comes out of the nozzle varies little during the course of the day, according to Consumer Reports, so there's little, if any, benefit, to getting up early to pump gas.