SPN-191 FMI 11 and SPN-158 FMI 2 error codes

2017 KW t680, cummins 2350, Eaton Ultrashift plus transmission. 375,000 miles.
I started the truck and it idled normally for about 30 seconds when out of nowhere it started idling up and down and the service light for the transmission and Warning message for Transmission Fault Service Immediately popped up. The speedometer started bouncing up and down at idle and I Immediately shut the truck off. After a few minutes I turned it back on and everything was back to normal. I pulled those two fault codes out of the system. Any ideas on if this could just be a one off or what might be wrong?

 

Still haven't found much online about this. Anyone have any ideas at all what the problem could be?

 

Unfortunately not. This was from when I first got my truck. After having the truck a little longer I found out the problem pops up only in wet conditions. The speedometer acting erratically happens very rarely but I almost always get a transmission fault code when it's wet out. I suspect I have a short somewhere in the speed sensor and/or xy shifter but since the code doesn't effect the trucks or transmission performance in any harmful way I've just learned to live with it as a gremlin. When I come due for a new clutch/rear main seal I'll probably change it out then and see if it solves the problem.
Sorry I don't have a better answer it's just something I've learned to live with on the truck.