I just found this on another forum, seems the new V-10 does have less HP.
Being a Ford retiree I still have some friends in low places at Ford, here is whats up with 2016 F-53 V10 HP and Torque numbers.
Short answer: New EPA emissions requirement for 2016CY applies to the RVs now (the specific requirement is grams of CO2 per brake horse-power-hour). To meet this requirement, the V10 output needed to be reduced. The engine and trans (hardware) are capable of carryover performance; The change to meet this EPA emissions requirement is the base causal factor.
