Okay here we go. I'll try not to leave anything out lol. About a month ago, I purchased a 2012 Ram 1500 Bighorn with 123,000 miles from a lot for a pretty good deal. Of course about a week after I bought it the PCM tripped a P0430 code, or bank 2 oxygen sensor 2 code, which I believe is the passenger side downstream sensor. The truck seems to run/perform great, although this is the first Hemi I have owned so I don't have much experience with them. However, it does sometimes seem like I can feel the truck ever so slightly shaking at idle. First, I knew the truck had the typical broken manifold bolt exhaust leak before I even bought it. I figured this was the cause of the code so I just waited for the new manifold, gaskets, and bolts to arrive to fix the issue. Turns out I had 2 broken studs on the driver side manifold and one on the passenger side. I welded nuts on the studs to remove them and replaced with new stuff and the exhaust leaks appear to be gone. Cleared the code and drove for about another week. Bam, tripped the code again. So this time I did a little playing around on my Bluepoint code reader and discovered that I could view live info from the PCM, including voltage data from the o2 sensors. Looking at this, I found that the bank 2 downstream sensor was bouncing up and down a lot, almost copying what it's upstream partner was doing. So armed with this information I decided to change both downstream sensors on the truck. I figured since the truck seemed to run good the catalytic converters were probably fine. Just put the two new sensors in today and the passenger side sensor does seem to be better but still seems to do more jumping around than the driver side. So could my converter really need replacing? Should I drive the truck for a couple of weeks and see if the code comes back? Seeing how there are no other codes indicating a misfire or something else that might cause this issue I'm not sure where to go at this point. Replacing the converters is pretty darn expensive unfortunately. I have heard people having mixed success with Seafoam and other additives. I did dump a bottle of Lucas deep clean fuel system cleaner in with a tank of gas today. What do you guys think? Thanks in advance!