I absolutely hate it when an engine is not clean internally. I also am very particular about feeling confident I am a great caretaker of my engine. And, my engine is stressed a lot more than a stock engine.

I hear so much about this or that oil is the best. I have no idea how anyone can be sure from driving experience. We know what our experience has been but we don't know if it would have been different using something else.

I say use a reputable synthetic brand in the specified weight that gives you warm fuzzies.

I use Royal purple and change it at 5,000 miles. I hear about oil lubricates better after it has some miles on it and that it is overkill and wasting money. My simple logic, or lack thereof, is that clean oil is not going to make my engine dirty. Besides, I really like the purple bottle with the yellow cap.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas