1. Open your fuel filler door and locate the fuel selector valve. It is usually located near the top of the fuel filler neck, and it is a small, round knob or lever.
2. If you do not see a fuel selector valve, then your vehicle may not have one. Some models of the 1993 F250 were not equipped with dual fuel tanks.
3. If you find a fuel selector valve, then turn it to the desired setting. The settings are usually marked as "Main" and "Aux". "Main" is the main fuel tank, and "Aux" is the auxiliary fuel tank.
4. When you turn the fuel selector valve, you may hear a clicking or buzzing sound. This is normal, and it indicates that the valve is opening and closing.
Here are some additional tips for using the dual fuel tank selector valve:
* Always turn the fuel selector valve to the "Main" setting when you fill up your fuel tank. This will ensure that you are filling the main fuel tank, and not the auxiliary fuel tank.
* If you are running low on fuel, turn the fuel selector valve to the "Aux" setting to use the auxiliary fuel tank. This will allow you to drive a few more miles before you need to fill up your fuel tank.
* If you experience any problems with the fuel selector valve, such as fuel leaks or the valve not turning properly, then you should take your vehicle to a qualified mechanic.
