If I owned an Ecoboost Truck Id feel as though Motorcraft Syn Blend might be inadequate for the task. Not knocking Motorcraft, it and the family of oils it belongs to (Kendall, Shield, Trop) are excellent oils, and I plan on using shield in my Ram, but I'd feel like it wouldnt be optimal for the turbo ecoboost application, especially when hauling.
For warranty purposes I'd find a full synthetic with a bigger dose of Moly, meets ford WS spec, and atleast an ACEA A1/A5.
Out of warranty? I'd use something like Redline 5w30/5w40, as it's on the thicker end of the weights.
Shoot, out of warranty I'd even look at something like Eneos Racing Street 0w50.
Are these trucks having issues with lubrication on the upper engine? I've honestly not looked much into Ford truck engines since the Mazda/Ford engine days.