Last August, I put some of that there Rotella DFA in my fuel for the trip to the Florida Keys. Everything was honking along just fine till after we got set up at Key Largo Kampground. On the way down, we seemed to have all the extra power in the world towing the 27' 5'er and 19' Lowe Deck Boat. We decided to go out and get supper and when I cranked the 5.9l Cummins, the Check Engine Light stayed on. Well, I shut down, let the oil drain back into the pan and checked it. Level was okay so checked the coolant, it was okay, checked the Power steering and brake fluids, they were okay. Cranked the engine, light stayed on. Called the DC Road assit number, gave them all the info they asked for, they told me to take it to the Dodge dealer in Homestead, Fl. They also told me it would be covered under warrenty. So I did, had to rent a car for 2 days, shop reset the light and told me the Cam Shaft Sensor was bad and not covered under warrenty. Shop also told me it would get us home to Georgia. Vacation went fine from that point on, just had to put up with the light. Got it home and to the shop, yep bad sensor, nope, not covered under warrenty (no lubed part), problem caused by adding Rotella DFA. Now, I would not trust this dealership here for nothing. But, if that is what they said, you think I would put anymore in? Not in this lifetime.