What is the difference between standard Mobil 1 and the Mobil 1 for SUV's and Trucks? I understand that the additives are probably different, but they are both 5w-30. The SUV/Truck one says it is for extreme service though. So I am thinking that since I do 10K OCI that it would be considered extreme service and that I should use the SUV oil...even though it will be going in a 4 cylinder passenger vehicle. Any thoughts on this?