Now it has switched to 5 and 2. So I'm cleaning throttle body and resetting as well as running Seafoam through it on my next drive.
Throttle body was medium dirty.
The Long term fuel trim is staying near 0 or running -3.9 sometimes. I'll watch it when I drive.
The plugs looked great both times I had them out.
No coolant leaks, no using oil.

Is there a way to know if Cat is plugging?

 

Plug a gauge into the exhaust before the cat. Anything over 2 PSI at idle, and the cat is on its way out.

 

the -3.9 long term fuel trim is its responce to the repeated misfires... its trying to take away fuel. if the cat was plugging it would really die out at the top end... hey you makes a good point with cylinders being next to each other you could have a head gasket leak between the two cylinders allowing the compression to escape out the other cylinders valves without loosing or contaminating fluid... i would check it with a leakage tester.

 

Finally getting back to responding to the fix for this.

I did a complete re-route of the plug wires per a service bulletin from dodge that I located here TSB 18-48-98

Here is a thread:
https://dodgeforum.com/forum/2nd-gen...lug-wires.htmlhttp://https://dodgeforum.com/forum/...lug-wires.html

This did the trick but interestingly it took a little while for the truck to quit throwing codes. This took a little time and but the instructions are exact.

Thanks for all the help on this, it was tricky but in the end a simple and obvious fix.

 

I like the simple ones..... thanks for reporting back.