had to have both exhaust manifolds replaced and then i was told i need to change my o2 sensors so i saved myslf even more money by purchasing and replacing those my self. it started a few days afterwards the misfires and the check engine light came back on with the codes p0420 and p0430. not sure what else the problem can be. my warranty is expired and from what i read online on other dodge forums there is a problem that dodge seems to be ignoring with there motor on the durango. most likely the last dodge i will ever own after i get this fixed. they already had to replace my gas tank because that issue and now i am having this problem.