Droning noise from rear.
 

Hello, I have a 2004 X type 2.5 manual with 82000 miles.
Since January, have heard a droning noise between about 20 to 50 MPH from what appears to be the rear left of the car. Could be wrong.
In the cold weather, I still get the "wine glass" noise, so whatever causes that, does not seem related to my problem. Noise does not change, steering left to right or accelerating or decelerating. Uphill downhill. Frequency changes with car speed. Hot or cold. In any gear or neutral. Still there.
Over the past two months I have:-
Changed discs and pads.
Swapped tyres.
Checked the gearbox oil level - all good.
Checked the transfer box level- all good.
Injected the carrier bearing with grease.
Checked the diff oil. Needed about 0.5 litre.
Changed left rear wheel bearing,
Noise is exactly the same.
Any suggestions would be appreciated.

Check to see that all of the exterior body plastic is properly attached. Airflow might be vibrating a loose part.

Checked plastic panels, things in the wheel well. Still stumped. I'm hearing this noise in my sleep.
Had a good look this weekend.
Everything seems good apart from I can feel, see, and hear some lateral play where the rear of the propshaft enters the flange on the diff. It is definitely there. I assume it's just a splined shaft with a nut inside. Does anyone know for sure? Is it possible the nut has come loose? After 14 years.
Is it even possible for this part to wear?
Thanks in advance for any comments.




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