My 2008 Nissan Navara D40 YD25 alternator started making a cooked bearing noise, I stripped down the alternator and found the rear bearing was the culprit, about to fall apart.. I replaced all bearings and belt, it is now running like new.
Not shown in the vid - There is a small hole at the rear of the alternator to insert a pin to hold the brushes back during reassembly.

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