I have a 2004 GMC Sierra with a Duramax/Allison. Today while driving, I noticed white smoke as I accelerated from stops. The problem seems so bad that people move from behind me to pass and stay out of the smoke. I have not noticed anything like this in the past. I still seem to have great power and acceleration. I do not notice any performance loss. I recently switched to Rolling Big Powers Diesel Additive which I mix with Amsoils Diesel Concentrate. I had been running the Amsoil Diesel Concentrate before with no problems. I dont know it that has anything to do with it, but I kinda suspect that something is not right. Please give me some insight to this problem. I would like to get it corrected before something major may happen. I also still see the black smoke on heavy acceleration. Thanks in advance for your help.