basic diy
BMW TIS - 00 00 249 BMW engine oil service (M60 / M62 / M73)
you might find more on this forum by using the search or articles tab at the top of the page .
here is a diy on a 3.0i engine . the procedure is almost identical
http://www.xoutpost.com/articles/x5/...w-x5-3-0i.html
bmw uses castrol synthetic oil 5 / 30 or 0/30 or 0/40
mobil 1 oil is acceptable
the drivers handbook gives info .