Hi Mafian, although I don't own an X5 any longer ( traded ) I still find myself gravitating back to this site frequently, if only to lend some advise where I can. So my suggestion as a must would be to check the cranckcase breather as on your year model it has the old version which is prone to clogging and can cause seal problems due to excessive crankcase pressure. the updated version does not contain a filter. Congrats bye the way.