Hey. I just got and 04.5 Chevy duramax from my sister. It has 96k miles on it dead stock minus a preditor tow tune. The other morning it was around 30 degrees out and I fired my truck up and it sat for about 25 min. most of the time it was in the warm up mode. I hopped in the truck and drove down the street and the truck was pumping out a cloud of blueish white smoke. It did this for about 1 mile. After that it cleared up. Is this normal? Thanks

-Lucas