WATCH: The Reason Cars Have Gas Tanks on Different Sides
It's reasonable to assume that something as essential to a car as its gas tank would be closely regulated by manufacturers.
On the contrary, there are no regulations that specify where a fuel door should be placed in the United States. In an interview with Allstate, Ford spokesman Mark Schirmer explained that car-company engineers can place the door to the gas tank on "whichever side offers the easiest packaging."
It's sort of funny to think that such a big part of our lives (the average American driver uses 656 gallons of gasoline each year) could be decided on a whim, right?
According to Nissan's Communications Manager Steve Yaeger, it's actually a lot more complicated than that. "The placement of the fuel door is mainly a factor of fuel tank design, location and underbody packaging," he told Allstate. "With all of the structure and components located underneath the vehicle, (engineers) would quickly encounter restrictions in trying to route the filler tube to the same side on every vehicle."
So, for example, if there's something like a big speaker must be placed on the left side, the fuel door will be moved to the right. Schirmer noted that most Americans prefer to have the fuel door on the left, but if there's a valid engineering reason to put it on the right side, that's where it will go.
And if, like us, you're prone to forgetting which side of your car your gas tank is on, or you frequently drive rental cars, look for the hint built in to the dashboard of each vehicle. The little arrow on your fuel gauge will never let you down.