I bought a 2005 Durango Limited with the 4.7L because my car was in the shop and I needed a way to get to work. I picked it up from a neighbor for $1200 knowing that it had issues but would still run and drive around town. All in all I feel like I got a good deal, regardless of what the issue turns out to be.

Now for the issues: I have to select 2 for the transmission to shift at all. If I choose D I am stuck in 1st gear and it won't up shift at all. If I choose 2 it will shift between 1st and 2nd gear. This means I am sitting at 3500(ish) rpms to do the speed limit around town. If I get on a good hill and let it pick up speed while coasting it will buck and fight and generally pitch a fit if the speedometer tries to go over 55 mph regardless of how I get it there. I think there is a circuit grounding out somewhere. When I turn it off the headlights continue to flicker for several minutes afterwards. When it is running and the headlights are off, they still flicker. I have a CEL that never goes away regardless of whether I clear the codes or not. It is something related to the heated O2 sensors. I was going to start by inspecting the wiring related to the headlights and O2 sensors. The only thing I can think of that they share is grounding. I am going to replace the battery and probably the ground wire coming off the battery.

I am looking for other suggestions for where to begin. It stands to reason that there could be an electrical issue with something transmission related, but all of my specialized automotive knowledge starts and ends with German sedans. I know the basics that apply to nearly all ICE's but I know very little about Dodge motors.

Thanks in advance everyone.