The fan that you are video taping is not the Aux fan. That fan is the fan attached to the engine water pump.

The Aux fan is in Front of the radiator. If the noise is coming from the fan that you are taping, could be a bad bearing in one of the idler pulley or a bad tensioner. Worse case scenario is that the bearing in the water pump is shot.

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2006 Infiniti G35
2001 BMW 3.0I E53 X5 Build date 08/2000 SOLD
Lotus Europa 1970 Destroyed by fire
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