This Ford F150 has had a weak cylinder at about 16000+ miles, we replaced the engine because of this, the "new old" engine had approximately 139000 miles on it. Replaced alternator twice, batteries a few times, the rear fender on the passenger side fell off Thursday when my dad drove it to work (9/21/06), replaced fuel pump, rear gas tank has a leak, faulty windshield washer connection, replaced radiator (not sure how many miles), had this truck for many years and it still serves its purpose. After we replaced the engine it ran fine for a few days then it started to high idle even after it was warmed up, still need to fix that.
Nice truck, workhorse, interior is in EXCELLENT condition, very clean, four wheel drive still works.
Also would like to add to this comment that I fixed the problem with the "high idle", the throttle positioning sensor was bad and I just replaced it with a new one, now it runs great!