My girlfriend works for a great mechanic and she said they had another F-150 in today with the 5.4 Triton engine that needs the plugs changed out. She said she always feels so bad for the customers when she has to explain that the plugs are prone to break in the heads and that it will be an additional hour per broken plug to extract. She also said the newer Ford vehicles with the direct injection that goes straight into the cylinders has problems. The design causes excessive carbon build up in the engine since it by-passes the plugs. There are TSBs online that every 6,000 - 12,000 miles you have to tear down half of the engine to clean out the carbon. Ford will not warranty this work. How wrong is that? I bet the salesmen don't divulge this info when selling the vehicles.