I have been driving a 1985 Land Cruiser for 24 years. I have run out of gas in it 3 or 4 times. The manual says the gas tank hold 22.2 gallons, and I have put in 22.1 at least a dozen or more times. I am not worried about the crud in the bottom of the tank because this vehicle has a fuel filter. I have never burned out the fuel pump because it is next to the motor and gets hot all the time. I think fuel tanks have baffles in them to greatly minimize the effects of going up hill or downhill.