Ive had Ford diesels for years and always used some kind of additive.
On my 2017 , dealers says NOt to use anything.

 

Dealers? They know less about their product than we do. Look at all the RV dealers that tell you your truck can tow that, no problem. You dealer doesn't understand that US diesel fuel doesn't even meet the diesel engine manufacturers standards for lubricity, and that fuel at many stations doesn't even meet the US standard for lubricity or cetane.

 

I did a bit of research before choosing PM22-A. One of the things I learned is that some of the fuel additives encapsulate water. This allows it to pass the 1st fuel filter / water separator, into the fuel system and eventually into the cylinder so that during the power stroke it's turned to steam and passed out the exhaust system. From what I've read this is bad. All of the water doesn't make it all the way through and what does eventually causes exhaust system issues. Of course this is not going to happen over night. If you plan on keeping your truck for a while you probably want to look into which additive you're using, if you plan on selling your truck before it's life is over you may want to consider those of us that buy used vehicles.

 

The process of assisting water to mix with fuel is emulsification. You want your additive to be a demulsifier so that water is more readily filtered out.