Originally Posted By: Quattro Pete
AFAIK, fuel is being picked up by the fuel pump from the bottom of the tank, so even if your tank is full, the stuff at the bottom would get sucked in first.
The main reason it's advisable not to run on fumes is to protect the fuel pump. In some applications the fuel pump is cooled by the surrounding gasoline at the bottom of the tank. Now, if there is very little fuel left, the pump is not submerged and may overheat and fail prematurely, but personally I never had that happen to me either.
Originally Posted By: mechtech2
Debris DOES settle to the bottom.
Whether empty or full, that's where any will be.
What good is full or 1/4 full for this?
I usually just fill it up, then drive till it's way down.
People that think letting the tank get below 1/4th full will suck up the stuff on the bottom of the tank obviously don't know how a fuel pump works in the first place. It's sucking up fuel near the bottom AT ALL TIMES!
As stated previously, the main reason why it's recommended to keep the tank from getting dry is to cool the fuel pump (if it's internal) but even then, the auto manufacturers prevent this by leaving a gallon of gas in the tank even when your gauge says you're empty.
It's an old wife's tale that doesn't apply today with high quality control at the gas pumps as well as your car's lifetime fuel filter.
It's the people who forget to close their gas caps and end up driving around with it wide open, allowing for stuff to get in the tank that started this
MYTH!!