Diesel Bombers - 1998 Cummins Power problems

hey people i have a 1998 dodge ram 2500 and just this week since i live in illinois it has been getting wickedly cold outside, my truck seems to be losing all power to drive normally back and forth to work. I have never rode it very hard at all the man who owned the truck before me was a farmer and he took great care of his truck. I am just questioning what is going on wrong with it i dont have any idea because i warm my truck up for about 10 minutes before i leave. please email me for any suggestions and ideas! or text me at 985 855 5440