The older Modular engines, early as 1991 in the Lincoln Town Car, 4.6, 2 valve, were good.
F-150's got that engine in 1997 and the 5.4, 2 valve, 1997 through 2004, known several people who have put 300+K miles on them. One guy Gene, owners a residential vinyl business, 455K miles and the differential went out. Never changed the oil because the owner's manual says ''good for the life of the vehicle''.
Steer clear of the 3 valve engines.
Bristoe, a friend of mine had one of the year trucks that had gasket problems. He said the mechanic said the gaskets were shot, I said - what does that mean? reply > time for a new engine, $3000 installed, that was many years ago. Runs like a sewing machine now, says he's going to drive it until the wheels fall off or he kicks the bucket.
