I too replaced the clutch fan with an electric one with a controller to set the temperature the fan comes on. I have it set so that it comes on just before the electric fan in the front of the radiator engages. I have it wired so the fan comes on after the key has been removed as long as the radiator temperature continues to exceed the controller setting. Have had it in place, I'm guessing, almost two years. I had to replace the controller last week because it fried but that is the only issue I have had.

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