Yeah, I am not quite buying that...
First, getting a Ford Dealer to do warranty work is tough and a long wait. Technically (if it was my dealer), even after 7 years he should be waiting on engine #2. I was just quoted a 2-week wait to replace a wheelbearing
Maybe, MAYBE he is getting substandard repairs on his truck, otherwise three engines is a tough sell. One replacement engine, sure... but two? That screams abuse... or really shoddy mechanics.