Rant: I reused head bolts on a 4.6 for years, then one let go at 60k
I always figured torque-to-yield bolts were just a suggestion if they looked clean and felt tight going back in. Then a customer's F-150 in Garland came back on a hook 60k later with a blown head gasket and I knew it was my fault. Anyone else learn this one the hard way, or am I the only one who skipped the new bolt kit to save the customer forty bucks?