Guys I recently had the experience of a lifetime. My dad recently passed away so me and my family had to travel from Oregon to New Jersey. As I was passing through Iowa I stopped at a rest area to stretch and that stuff. Well when we all loaded back into the Expy I got on the interstate and the engine started sounding like the exhaust manifold cracked or something. It was really loud almost like an unmuffled lawnmower. It was around 12:30AM so we had to wait until 7:00AM to get any service. I called a full service garage and told them what had happened and what I thought it was and they referred me to this exhaust shop. So I had the Expy towed and they looked at it and told me the exhaust was fine and thet the engine had blown out a spark plug. They could not fix it because they were not equipped to do that kind of work. So I had taken it down the street to a NAPA car care center and it took them 3 hours to remove the rest of the plug and install a new one. They told me that the threads were stripped and they had to put a helicoil on the new plug. I was wondering if this has happened to any other Expy owners out there? I spoke with a friend of mine who is a mechanic in North Carolina. He told me that this is a known issue with the Ford 5.4 and the 4.6 engines.