Since source of oil leaks can be so misleading I always get the vehicle up on jack stands and clean the engine top and bottom. Once that is done I let the engine idle up to operating temp and then with my handy dandy super bright focused beam flashlight lie underneath in wait for the highest source of fresh oil to appear. Sometimes I have had to run the RPMs up to 3000 or so and hold it for a minute or two when it hasn't shown up at an idle after 10 minutes or so. If the leak is significant enough that repair should be done that process almost always confirms the source.

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