Damn...I just poured through the '07/'08 E70 Manuals, handily found
on the front page of this site and, there are
no oil capacities listed. 
Kowabunga: we are truly in the age of TurnKeyLease'Em & Leave,
for the Biff&BuffyBrigade.
From my memory, my '01 3.0 takes 8 qts...and the 4.4 V8s take 8.5 qts.
I'd bet the 4.8 is real close to that 8.5 quart req'.
The poster that suggested "5 qts" must have just gotten off his shift
at the QwickLube,
No oil capacity...we are WalmartNation. Shame on BWM, imo.
BR,mD