The 4.6 L is a great engine and you can get 250,000 to 300,000 miles with no problem (with maintenance).
The 4.6 L from the factory uses hypereutectic pistons and one of the areas of concern is detonation - the piston can fracture between the top and second compression rings (ring land). This will not be noticeable during driving only on oil consumption. It is the beginning of a more serious condition later. I’ve seen an engine run for 50,000 miles with only oil consumption complaints. I have pictures of this somewhere, if I can find them I will post them.