THE NEW STYLE STC FITTING THAT FORD JUST CAM OUT WITH WILL ELIMINATE THE NEED FOR PROACTIVE REPLACEMENT OF THAT PART!! INSTEAD OF USING AN O-RING, THE HAVE JUST MADE IT WITH A JAM NUT. THIS WILL HELP PREVENT IT FROM DYING ALL OF THE TIME. THAT IS THE MOST COMMON PROBLEM WHEN THERE IS A HIGH PRESSURE OIL LEAK. ANY GOOD TECH SHOULD HAVE IT DONE WITH IN A DAY!! ALSO, IT COULD BE THE D-RINGS ON THE DUMMIE PLUGS IN THE HIGH PRESSURE OIL RAILS. SOMETIMES THEY HAVE A TENDINCY OF GETTING CUT. IF THAT'S THE CASE, THEY WILL JUST HAVE TO WHIP THE VALVE COVERS OFF AND GET THOSE D-RINGS REPLACED. A FEW HOURS MAX FOR THAT REPAIR. (IF THEY HAVE A DECENT TECH!!)