if you go to the online parts database and input data that fits your cars mfg date...the diagram only list a 4,10 diff (you can click the link that says "select another car" and then enter the last 7 digits of your VIN to get a more specific parts diagram): http://www.realoem.com/bmw/showparts...04&hg=33&fg=05
Bmw diffs that are LSD (limited slip diff) ...they have an <b>S</b> in front of the ratio...it would read S 4,10 on the diff's tag.