How is the Eco Boost in the western mountains?

I pulled my 5000lbs+ 24' HTT, with a 5.3 Avalanche, through the Sierras, Cascades, Rockies and Siskiyous for 10 years.
Never had a problem.

I now have a 26' TT that weighs more and has a heavier tongue weight. The Avy struggled some, enough that I replaced it with a 2014 Ecoboost with Max Tow Package and more payload.
Haven't drove the combo through the mountains yet, but I am very confident it will handle the trailer easily, going up or down the mountains.