I am new to the diesel side of things and I got an 03 duramax about 6 months ago. It started to blow white smoke after working hard towing my dune buggy around. I brought it in to the dealer and they said that cyl. 7 injector has a high balance rate and needed to be replaced. I decided to just leave it alone after them telling me $1500 to change just that one. I bought a predator and checked them with that and they are all within speck mostly around 2.5. I checked it in park at normal temp. it still smokes when it idles but usually after driving alot. What should I do? I am going to be driving this 4 hours to chicago from michigan for the next year and a half for school and I dont want anything to happen. Any input would be appreciated, Thanks.!!