How often do you fill up your gas tank? I normally do it when it's half tank. Anything lower makes me nervous

That the thing with low displacement cars (at least for me). I try to squeeze as much power from them and that means high revving and shit MPGs. That's why after my civic I changing for something bigger, where I can go fast without forcing the engine too much

I let the fuel run down to where the needle is halfway between the 1/4 full and Empty mark. There is no need to always have a tank nearly full because I would be carrying around a lot of extra weight. Over the entire year, you're going to lose a bit of mileage due to that weight.

The main reason why I bother to fill up to full is because I write down my mileage. That's one of the aspects of how I keep track of how much wear and tear is going on with the engine and powertrain. If I see a sharp drop in MPG then I know something is wrong. If I wasn't keeping track of such stats, then I'd never really fill more than half full because there's no need to carry extra weight to cause more wear and tear and loss of mileage.

For those afraid of grit in the last little bit of fuel, you know, you could just let it run right up to Empty and then siphon out the last bit of stuff in the tank to see if there is dirt in it. Then pour in that gallon or three of gasoline from your external gas can and drive to the gas station to fill back up. That way, you've siphoned out the dirt or sludge in that last bit of gas at the botttom of the tank.

No Hello Kitty branded gasoline. But Hello Kitty motor oil exists...

Any large SUV easily ballparks 6k+ pounds. A Hummer H1 can get as heavy as 8k pounds. A Lincoln Navigator is about 6k pounds itself.

I tend to keep it near full, but as a pizza boy I do 20 miles one night, then 150 the next so I have to be ready for that shit