There are a few reasons that some pickup trucks have two gas tanks. The most common reason is for increased range. Having two gas tanks means that the truck can travel further before needing to refuel, which can be helpful for long trips or when driving in remote areas.
Another reason for having two gas tanks is to provide a backup in case one tank runs dry. This can be especially useful if you're driving in an area where there are no gas stations nearby. Having a second tank gives you a safety net in case you need it.
Finally, some people simply prefer the peace of mind that comes with having two gas tanks. Knowing that you have twice as much fuel on board can give you an extra sense of security on the road.
Overall, there are a few reasons why some pickup trucks have two gas tanks. Whether it's for increased range, safety, or peace of mind, having an extra tank can be helpful in many situations.