Originally posted by: ariafrost
OMG
I'm seventeen years old and know more about cars then the majority of you guys here... that's pretty sad, considering I don't even drive yet! (No car, meh)
First of all, there is no real harm in driving a car down to below 1/2 a tank of gas... the only thing that would harm a car is if you completely RAN OUT of gas... so you should prolly fill up at 1/8 of a tank or earlier (earlier if you want to make sure you don't run out if you have an emergency or something)...
One other thing I think no one has mentioned is that if your tank is 1/2 full as opposed to full, you'll get SLIGHTLY better mileage due to the lessened weight of the car (and slightly better accel, more effect the larger the gas tank). So in terms of mileage, it might help minimally not to fill up all the way. What my friends usually do is just buy $5 or $10 worth of gas unless they're at <1/8 of a tank. Doesn't really save money, but oh well... makes it seem like you're spending less...