Strange liquid leaking over rear diff - X5 E70 2009

[DjfLoYd]

Hi guys and gals

So I'm having a strange leak that, at first glance, appears to be the rear diff but it isn't.
I've had the rear diff checked and none of the liquid is coming from the rear diff but rather, seems
to be dripping onto it from above. It then flows down the diff and gets sprayed along the rear, underside
of the car. It only appears while or just after driving it seems. It's not a constant leak as far as I can tell.
I've had the diff emptied and re-filled and both times the correct amount of diff oil was still in the diff
and then refilled. Just under a litre or so. So I don't expect it to be an overflow/over filled type issue.

I can't see any sign of this liquid towards the front of the car.

The liquid is low viscosity, reasonably clear but oily. I can't recall it having a particular smell.
It looks almost like brake fluid or newish diff/gearbox/engine oil.

Are there any sort of liquid-carrying lines that run over the top of the rear diff that might cause this?

I'm really stumped.

Thanks for any insight that might be forthcoming.

 

[AlexYannoulatos]

Some mounts are oil filled, maybe this is the case where it is leaking and sits higher above or near to the diff.

 

[Gordvisr]

Hallo
You did not mention what the exact model yours is. Best way to find out is to use realoem site, use the site with your car's vin number and check the diagram to see what diff you have, diffrent models have diffrent diffs, diffrent type of rear suspension.