Researchers say those who manage gas stations know this but they probably won't tell you that there is a best time of time to fill up your car.
They say the best time of day to buy gas is between 8 am and 10 am, because that's the time gas station managers are going around check out the prices of their competition.
If they are going to raise the price, they often do so between 10 am and noon.
The best day of the week they say is generally Wednesday, since prices are lowest then.
Gas prices tend to get higher closer to the weekend, especially holiday weekend.
Prices tend to go up on Thursdays, just in time to start the weekend.