I HAD JUST GOT OFF WORK AND WAS LEAVING THE PARKING AREA AND BLEW OUT THE NUMBER 4 SPARKPLUG ON THE RIGHT SIDE HEAD. I SHUT OFF THE MY TRUCK AND PARKED IT. I CALLED A FRIEND THAT LIVES CLOSE FOR A RIDE HOME. THE NEXT MORNING I DROVE BACK TO THE PLANT AND TOOK MY TRUCK TO THE LOCAL FORD DEALERSHIP. THEY SAID THAT I SHOULD REPLACE THE HEAD OR INSTALL A HELICOIL AND ALSO REPLACE THE SPARK PLUG AND COIL PACK. SO I HAD THEM INSTALL THE HELICOIL AND REPLACE THE DAMAGED PARTS. LESS THEN A MONTH LATER I WAS DRIVING TO WORK ON THE I 90 AND I BLOW OUT THE NUMBER 5 CYLINDER SPARK PLUG AND THIS TIME IT TOOK OUT THE PLASTIC SHIELD AND RIPPED THE SPARK PLUG AND THE COIL PACK OFF HE TRUCK. I HAVE NOT DONE ANY THING BUT CONTACT FORD MOTOR COMPANY ABOUT THIS AT THIS TIME. THERE SUGGESTION WAS TO REPLACE THE HEADS MY SELF AT A COST OF 6,000 DOLLARS. *TR