He also used to go 50k between oil changes, just adding oil. Near the end, it was burning a quart with each tank of gas. It was also a 2 valve 5.4 with no finicky variable cam timing.

 

And a majority of it was highway.

 

Sometimes, it's all a matter of using whatever I already have on hand. Right now, I'm looking at 3 quarts of Mobil 1 5W-30 that is leftover from......I don't remember what. I've also got a few cases of Castrol Magnatec 0W-20 which was on sale from Amazon ($20 per 6 quart case). The plan for the Castrol is my Transit Connect. But I'll probably pour some into the F-150. Maybe even mix 3 quarts of it with the Mobil 1. Although people say not to mix oil.....I've done that before also. Nothing bad happened. I can't recall how many times there was 1/2 quart leftover after changing oil on a Honda, and I just poured the extra 1/2 quart into the F-150. It's fresh oil, and brought the level on the dipstick up. Good enough until the next oil change.

5W-20 is in the manual. Now, on a lot of Fords, the manual actually says that you can use 0W-20 as an alternative. I've also read where people use 5W-30, since 30 weight oil was what Ford recommended before 20 weight oil.

I've used 5W-30 & 0W-20. Honestly, I couldn't tell any different. Truck still drove the same, and got bad mileage. 0W-20 did not improve my fuel efficiency. I don't know if 5W-30 gave me any added protection.