At the top of this great site's page is a tab that says Online References; hit the tab, drop down, see PDF Docs. Click on E53 Ref Docs, first line: up pops a list of Model Year Manuals. Click on yours, 2002...it is the entire Manual.
Try the Index, a handy thing: see Capacities, page 173.
It is 8 qts, pasted below from that source.
GL, mD
Engine oil and filter change quarts (liters) 8.0 (7.5) – BMW X5 3.0i