I am really coming to the end of my patience with this truck, I have had so many problems it is beyond a joke (check out previous posts if you want)... Now I get the light on again, mechanic at local shop pulls the code P420 or PO420, cannor remember which, he says it is related to the cat converter. Has anyone else has this? It is a 2005 LE Crew Cab with 67,150 miles. I need help on this folks.