FCA recommends it to be used under 30, as noted here:
https://www.ecodieselram.com/forum/threads/r51-fca-recommends-a-winter-front-cover-for-colder-climates-with-ecodiesels.521/
Here's a great thread for you! Welcome to the forum (y)
https://www.ecodieselram.com/forum/threads/ram-ecodiesel-oil-change-information.318/
also this: http://www.ecodieselram.com/forum/threads/psa-fca-changes-oil-specification-requirement-for-ram-1500-ecodiesels.820/
Good info.. looks like it's for Windows and/or Android software. Looks like $49 for the cost, and the adapter is here: http://www.alfaobd.com/index.html
Could always get a smaller one: https://www.amazon.com/dp/B008SEBQ2G/?tag=jhdiesel-20
But, you're not going to get the stations like before. I don't use FM radio anymore so it wouldn't be a worry for me..
Anything can be detected by the dealer if they want to find it. As far as tuning, it's really hard to beat custom tuning with a reprogrammed ECM. I think you'd all around enjoy it more.
We've got plenty of reading on that here!