can you use 10W-30 synthetic oil in a 2004 BMW X3
Yes you can. Check out this site to see which weight oil is best for your engine. http://www.bobistheoilguy.com/motor-oil-101/
In deed. Castrol is recommended, but Royal Purple and AmSoil are pretty darned good in my book.
By using a different weight oil then BMW recommends your could start consuming more oil then if you used 5w30.
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