Help w/rough start 04 Xcursion

[Farmer11]

^^^ exactly what he said. I had the same problems with my 03 F350, did this, and now its like a completely different truck. I know its maybe hard to believe that a the oil additive makes that big of a difference, but within 2-3 minutes idling i could already hear the difference in the motor. much smoother, no knocking. I took it out for a test drive, put it to the floor out of the driveway and it took off like the engine had been hot already.