Many times clutch fan performance will degrade over time, not just fail all at once. When it loses significant cooling capability the electric pusher fan will run more. It is intended to be supplement cooling, like when the AC is on, not as a primary cooling source.

A decent electric fan can be set to start up based on radiator temp. They have a dial to change the setting where you choose. I have it set to come on just before the front electric pusher fan engages. Have been running the electric fan in place of the clutch fan for several years, very reliable. Cost is reasonable. I did have to replace the controller once but it was not expensive at all.

Replacing the clutch fan with an electric fan extends the life of the fan in front of the radiator and reduces heat sink as you can wire it to run after the key is removed, until the radiator reaches your setting where it turns off. Frees up a little HP/TQ but stating how much will start an argument. I have been using electric fans for decades on modded cars. Simple install, simple tools any DIYer will have. Doesn't cause any error codes. Not pitching electric fans, just informational. Clutch fans have been around over 50 years. They work fine and last a long time.

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