Mobil 1???
 

I have been changing my 05 x5 engine oil using mobil 1 5w30 synthetic but BMW recommends using bmw synthetic oil... whats the difference between the two? i know that mobil 1 is a great Synthetic oil.. Also when i bring my car in for 15000 service they will change the oil with bmw synthetic oil.. does it matter using differnt oil?

All automotive oils MUST conform to the API (American Petroleum Institute) "Engine Service Classifications" (SA, SB, etc., etc.). API dictates that oils of a specific classification MUST be miscible between brands without deleterious effects. So the answer is that synthetic Mobil 1 5W-30 and synthetic BMW 5W-30 are COMPLETELY miscible/interchangeable.

For what its worth, I personally use Mobil 1 15W-50.

Everything you'd ever want to know about motor oil thanks to withidl, one of our very own members here at X5world :D - http://www.xoutpost.com/articles.php?...icle&artid=208

It doesn´t matter to use different oils. But I recommend you to use the mobil1. It´s the best!

I dont believe BMW make their own oils!So,BMW synthetic oils are probably refined by Mobil or Castrol anyway......

maybe this can help you. it´s a file from bmw which oil you can use for all bmw ;)

hmmm the files shows 0w40??? i just use 5w30 syn.