Plenty of opinions here: https://www.ecodieselram.com/forum/forums/ecodiesel-performance.28/
I always like to give the truck a few minutes to warm up.. since your way up north, I would suggest the same!
Welcome, I would consult with a lawyer that specializes in lemon law for an idea if it's something you should proceed. Either way, since you are this deep and obviously not happy I would cut ties if you can't get out of it via legal action.