When the fan coupling is cold it should spin fairly easily for a unit that is broke in. Use a hair drier or a heat gun to warm the coil on the front of it and see if it still spins freely. If it locks up or drags it should still be good.
If you replace it, it may sound like a jet taking off. This is typical until it gets worn in.

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2003 X5 4.6is Estoril Blue
2005 Infiniti G35X
1972 Datsun 240Z
1991 Isuzu Impulse XS Sold
1972 Fiat 850 Spyder Donated
1972 Datsun 240Z Sold
1972 Datsun 510 Sold