During high external temperatures I hear a fairly loud fan come on for a period of time and then turn off. is this normal? 2013 Tahoe LT with 45,000 miles and always serviced by Chevrolet as required. Thanks. Bob
Thank you for writing in. Yes, it is completely normal for a cooling fan to turn on in order to help reduce the temperature of the engine. It will kick on once the engine reaches a certain temperature. It runs until that temperature is reduced, or until timed out by the vehicle's computer system. You may notice that it turns on often while you are at a stop, as there is less air flowing through the radiator helping to cool the coolant in your system.
However, if the fan is making extra noise, then it may be a sign that there is an impending issue. For instance, if you have been driving the car for months or longer, and you just now are able to hear the fan louder than usual, then it may be starting to go out. Fans do not typically fail this early, but it would not be unheard of. It is more likely that you are just now noticing the fan kicking on, or that you have another issue that is causing the engine to work harder and amplifying the fan's usage.