Thanks for posting, but for the Ecoboost, the Owner's manual specifies 5w-30 only. I run 0w-30 in the winter at my own discretion, partly because Mobil 1 certifies it as a replacement for 5w-30. I have yet to find a 10w-30 that is certified as a replacement for 5w-30. I know some people are running 10w and some are even running 15w-40, but they do that knowing the risks.
Found on pdf page 382: (also found in the table on page 415).
https://www.fleet.ford.com/maintenan...ls/default.asp
•Motorcraft SAE 5W-30
Premium Synthetic Blend
Motor Oil (US)
•Motorcraft SAE 5W-30 Full
Synthetic Motor Oil (US)
•Motorcraft SAE 5W-30
Super Premium Motor Oil
(Canada)
•Motorcraft SAE 5W-30
Synthetic Motor Oil (Canada)2
3.5L V6 EcoBoost™ engine
Look for this certification
trademark.
Use SAE 5W-30 engine oil
Only use oils “Certified For Gasoline Engines” by the American
Petroleum Institute (API). An oil with this trademark symbol conforms
to the current engine and emission system protection standards and fuel
economy requirements of the International Lubricant Standardization and
Approval Committee (ILSAC), comprised of U.S. and Japanese
automobile manufacturers.
To protect your engine and engine’s warranty, use Motorcraft SAE
5W-30 or an equivalent SAE 5W-30 oil meeting Ford specification
WSS-M2C929-A. Refer to Maintenance product specifications and
capacities later in this section for more information.
Do not use supplemental engine oil additives, cleaners or other engine
treatments. They are unnecessary and could lead to engine damage that
is not covered by Ford warranty.
Change your engine oil according to the appropriate schedule listed in
the scheduled maintenance information.
Ford production and Motorcraft replacement oil filters are designed for
added engine protection and long life. If a replacement oil filter is used
that does not meet Ford material and design specifications, start-up
engine noises or knock may be experienced.