But really a friend of mine has a pretty new duramax (non-dually though) and he got some kind of chip and exhaust. It dyno's to 700-800 ft lbs of torque and when you really step on it, it pours black smoke out just like that.

Would a modded BMW diesel do this? A healthy one anyway..

 

Cant watch you tube at work but no a diesel that smokes is a badly tuned diesel.