Brother had a nearly new 4.7 quad cab 2wd, with 4.7.
Ok fuel mileage, light loads towed OK,
But Heavy load...5K and anything but flat ground was a total waste of time.
He actually had to push it to overheat limit just to get a load of wood home from the lumber yard thru some hills... ( not mountains).

better off buying a southern or west coast second gen with 5.2 or 5.9.