It sounds like the noise might be coming from the rear differential.
It could be metal shavings inside the differential that is grinding against the gears.
Check the fluid for the rear differential. Look for any contamination like metal shavings.
Any time the fluid is or have metal shavings it needs to be changed.
Here is a helpful guide of how to service the differential:
Please let me know what you find.
Wednesday, October 13th, 2021 AT 8:21 PM