A lot of you don't understand motor oil.
The first thing to note is any reputable brand sells better oil now than you could get when the truck was made, unless you have a current generation Ranger.
The oil type is largely based on your climate, with a few exceptions, and not so much now as in the past. Ford still recommends 5w30 in the Cologne V6 engines due to the way the oil pump works. They may not be able to maintain adequate oil pressure with 5w20. For the rest of them, it doesn't really matter if you run 5w20 or 5w30. There is a slight advantage to 5w30 in very hot weather if you do things like driving your truck like you stole it over mountain passes in hot weather like I do. If you live in hot summer area of the country you can even run 10w30 without any problems because that 10w factor isn't going to matter unless it is cold enough to matter. And many people live in areas where 0w-something really doesn't matter because it doesn't get cold enough to matter. But, the slight advantage is lubricating overhead cams at startup...maybe. I say maybe because the oils now have additives to maintain a film on surfaces so there is lubrication available for that second or two after you start the engine.
The bottom line is running oils in the normal 0w-20 through 5w-30 (or even 10w-30 in hot areas) weight ranges probably doesn't matter for most applications. It doesn't matter if you run Kirkland, Castrol, Valvoline, or Mobil 1 because all those oils sold now are much better than the oils that were out when older vehicles were sold. For those of us who are cheap, like me, we can buy some store brand synthetic oil with the knowledge that the oil is better than anything manufactured 15 years ago. So, wait until Costco has the next sale on motor oil and spend $36 on two bottles of synthetic oil rather than $30 for some branded oil and buy a hot dog and a slice of pizza at the food court with the money you saved.