Buddies 06 dodge broke down on him

Guy I work with truck broke down on him tonight. He is in the process of pulling his travel trailer from Nebraska back to his home in Minnesota. Called me saying his truck started running real rough then started blowing white smoke. I told him sounds like injectors to me. He said he changed the fuel filter and it helped smooth the motor out a little. Took off and it started running like crap again. Thought I would post it on here and see what you guys think it mite be. Any and all help would be greatly appreciated. If anybody knows of and shops in Nebraska that would be helpful also. He's in north central nebraska