New to the forum, just bought a 13 ecoboost xlt 4x4 with 3.31 rear and must say it is probaly the best vehical i've ever driven! traded in an 04 5.3 silverado with 76,000 miles that ran great but no comparison to the f 150. What oil do you folks run ? I know forced induction is hard on oil and i assume the eco is no different. I was thinking pennzoil ultra or amsoil 5w30. Would rotella t6 5w40 be out of the question because of warranty ? thanks !