IIRC, some E70s have issues with the front drive shaft failing and the result can be quite destructive. But, the covers need to come off from under the car as the front drive shaft is only partly visible and rear one is (almost) completely covered. I'd also worry that, if you have an audible noise while driving, your mechanic should be able to diagnose it. If he can't, you need a new shop.....

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2003 4.4i black ext./black int./black headliner (kid's runabout)
2014 535d X-drive, M package, silver/black interior

Sold but not forgotten:
2009 E70 35d, black ext./black int./black headliner (sold 2021)
2006 4.8iS Le Mans blue/cream int./black headliner, SOLD in 2012 sadly...

Other hardware:
2015 Cayenne S (wife's new DD and definitely wroooommmmm)
2016 Tundra 1794 edition crew cab, luxo hauler
2005 Tundra crew cab, weekend hauler. Sold after 150k very happy miles.