Anyone see a warranty problem/hassle if I used Amsoil 15w40 synthetic with the Mopar filter and had it changed by the Dealer every 7500 miles (7500 is the longest for my truck covered under warranty)? Trucks a daily driver no hauling or pulling and not much city driving. I want to keep my 5 year 100K mile warranty in effect and don't want to fight with any dealers. What does the Amsoil synthetic cost per quart? Could the Dealer give me any problems about API certification? I have 14K miles on my truck now so I would have to wait until it is broken in before the switch to synthetic. What mileage would that be since I don't pull or haul with this truck? Thanks for your input.