I appreciate the responses but since the CEL went out and so far I have not noticed any drop in performance I am going to hold off replacing the cat. I had a local muffler shop take a look the cat and as far as they could tell, the cat was okay and did not recommend replacing it. They did recommend replacing the o2 sensor first if the CEL came back. How hard is it to replace the upstream o2 sensor on a 3.0 engine.