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Gas Level

My husband and I are having a debate about the effect of low gas levels on your gas tank. I say you shouldn’t let the gas get below 1/4 of a tank because it can screw up your fuel tank and lines and he says that is only if you leave it like that for like months and letting the gas level get low is no big deal. Which one of us is right?

Letting the fuel level get low and keeping it low in the tank will lead to condensation (water) build up thus polluting the gas.

This condition normally applies where the humidity combines with high temps.

it could also hurt the fuel pump. But the thing that’ll hurt the most is when you’re running really low, you need gas, but can’t find a station to get any.

Letting the gas level get low is no big deal. There is no way low levels can screw up your fuel tank and fuel lines.

Many folks habitually run their tanks to nearly empty between fill-ups and have never encountered any problems, not even in a lifetime of such habits. Other folks insist on refueling at the 1/4-tank mark. Their motivation is chiefly a fear of running out of gas.

Slightly below 1/4 of a tank shouldn’t be a problem. Running it on E can shorten the life of the fuel pump. And of course you’re literally at the bottom of the barrel, so you’re sucking up whatever crud lives at the bottom of the tank, without a quantity of fresh gasoline to minimize this or dilute it. If it’s a pretty new car, probably not too big a deal. If the car is more than a few years old, you probably do have some crud and sediment that will be sucked into the fuel system if you run it very low.

If the fuel pickup is always at the bottom, where it should be, won’t it always be among the crud regardless of the fuel level?

There’s a big difference in having that crud diluted with 10 or so gallons of gasoline, or just having an inch or so to draw from.