Brushless Motor Noise, Can anyone help?

[axial 4x4 crawler]

Hello,
I have an axial wraith with the tekin rs and a 13.5 turn motor. And one day is out driving it and I heard a very loud sound coming from the motor. So I took apart the wraith, took out the transmission all of that and when I had the motor out of the transmission, I turned it on and gave it a little throttle and It sounded like an airplane kind of sound, What does this mean? I run it sensored with a 2s 30c 5000mah venom battery and I don't know if the inside motor is bad, if the rotor is damaged, or if the sensored board is bad in the motor? Just to let you know I drove it really ruff that day, that might have something to do with it. As long as someone could tell me the problem I will rebuild this motor. Thank you for helping I sure do appreciate this a lot.

[Johnnysplits]

Bearings possibly

[axial 4x4 crawler]

Could it be the sensor board/wire? because I opened the motor up and no dirt or dust. Can you tell me what happened to those bearings? need to be replaced, oiled, or anything like that I would appreciate it thank you for your help.

[Charlie-III]

The bearings could be dry (they need a little lube), worn out, maybe they got dust in them (likely worn out then), etc.
If there are no signs of the rotor rubbing on anything or that something was inside the motor (small rock), then about all that's left is the bearings.

Like anything else, they need a little care now & then, can't just run stuff forever, doing no maintenance, and expect it to stay working.