In America, if a corner exists a company will cut it.

In the US only diesel gets its own pump, at least in my experience

Here's a pretty typical american pump: https://www.alamy.com/stock-photo-shell-station-gas-pump-135764267.html You can select diesel with the green button, which comes out of the green handled hose on the left, but any other option for regular gas (87/89/93 in that picture) comes out of the right hose.

(US) I've been to gas stations in big cities, small towns, little collections of buildings that have no official name but they have a dollar general and a gas station, etc...

I've seen several kinds.

Single hose to dispense 87-93 ("normal") gasoline, and one for diesel

One hose for normal gas, one for diesel, and one for high-ethanol

One for all gasoline types and one for diesel

One super fancy stainless-steel-clad gas station that looked like something from retrofuturism had 5 hoses, one each for 87,90,93, e15, diesel, and the farthest end pump had a line for kerosine.

Never seen a combined gas and diesel hose though.

In America drastically different fuels like E85 and Diesel are dispensed with different hoses as mixing those with normal gasoline or vice versa in the wrong system could cause damage. But when it comes to different grades of just gasoline it's all the same hose. E10 or E15 are pretty much standard in many parts of the Country of Corn (USA) so they are the primary form of gasoline available for normal cars.

Every fuel has its own hose and “pistol”. Each “pump” has two or three or four hoses.

While those do exist in the States too, a single hose and "pistol" is used for all grades of gasoline and the operator presses a button to select their grade of fuel. The only time there is a guaranteed separate is between desil and gasoline:

The button leads to some interesting minor social problems. The expectation is that the use uses their hand or fingers to press the button, but the buttons are usually disgustingly dirty, so that lead many to using the tip of the "pistol" to smack the grade of gasoline which may put a drop or two of gasoline on the button. So those that come next and use their hands end up smelling like gasoline.

No longer interacting with public gas pumps is one minor joy of driving an EV.

its a thing often in America, there's just 1 hose and you press a button to select what blend you want.

Imagine getting Diesel in Germany. “Sorry, that was actually 15 liters of regular gas. ¯_(ツ)_/¯”

Edit: Ok, it’s not as bad as I imagined, since this picture seems to be about E15/E10, not diesel/regular.

Federal law states the punishment is a bare bottom spanking.

😳

Probably nothing. I guess it's possible if you kept switching back and forth between pumping a gallon of premium and a gallon of regular on different pumps to try to steal a few dollars of higher grade, they can use it to give you a ticket, but I'm pretty sure they won't really care if you were just topping off a tank of gas with 3 gallons before a road trip.

The vast majority of cars run fine on 87 octane. If that's what you're using, then it really doesn't matter if there is some 89 or 92 in the hose.

You should be filling up closer to a third. The fuel pump is cooled by the fuel and letting the fuel run too low can cause more wear and tear on the pump, causing it to fail.

5l, just shy of one gallon.

5L can't be shy of a gallon. 4L is more than a gallon.

checks

Yeah, a gallon is 3.7854118 L.

Oh...wait. You're in Europe. I bet that you're thinking of imperial gallons.

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That's about 4.5 L. Still not the case even with imperial gallons.

When people are talking about gallons in the US, they won't be using imperial gallons. They're using the US gallon.

Portable US gas tanks are typically 1, 2, or 5 gallon.

I usually just grab a 5 gallon (about 20L) can to fill up my lawn mower, throw some fuel stabilizer in there, and then I don't have to go back to the gas station for a long time.