Here's Mike answer from 5star.

Drive train losses are more on the 6.2L truck vs 5.0L truck.
The 5.0L is very strong indeed. It has impressed me towing at its 8000 lb capacity when testing our calibrations.
Truck specs are :
F150 5.0 4x2 short bed 3.55 gear 235.75.17 tires
F150 6.2 Raptor 4x4 super cab 4.10 gear 35 inch tires

Hope this helps and you will be very happy with the new 5.0L it knocks down great economy for a truck 19-23 on hwy is what i have seen.

thanks
Mike