We see a plug blow out of a 2 valve 5.4 once in a great while, its not that common and its an easy fix with a new coil pack and plug all at once in that cylinder. 200$ repair usually. The extended plugs are in the 3 valve 5.4's 06 and newer. I dont think the 4.6's use those plugs? I dont recall ever seeing a 4.6 blow a plug out however and our county runs a huge fleet of fords be it cars or trucks, they've all put 150K easily on the vehicles without much issues. We see axle galling every once in a while where the wheel bearing rides on the axle but i'm convinced thats more for people that never change the differential fluid.
