Hey Blizzard! Called my friend over weekend and his 1999 Dodge 3500 4x4, Cummins, auto trans has 230k miles. He said the fuel additives prevent cold weather fuel gel and do a great job keeping injectors clean. Injector issues were the reason he tried their products and worked great. Also, he mentioned "stiction" which I think has something to do with internal parts rubbing against each other, such as starting a cold engine. He said the engine runs smoother and the accelerator response time is noticeably better. I have never heard of Archoil and wanted to ask if anyone has had any first hand experience with their products. They have a great website at archoil.com.