I have a 1998 BMW 323i and am getting ready to change to oil in it. When I look up what oil to use, some say to use 0w20, 5w30,0w30,0w40 what should I use?
Probably any good quality synthetic oil will be good. A post at a BMW Car Club of America forum states that "Mobil 0W-40 is the only BMW LL-01 approved Mobil oil sold in North America. It is in fact a Euro formulation and much different than the other U.S. Mobil oil formulations." So I would say in the absence of more specific information in your owner's manual or from BMW (most dealers won't know much about models that old), going with an oil that has BMW LL-01 approval is about as solid a recommendation as you'll find.
https://www.bmwcca.org/forum/index.php?threads/best-oil-1998-bmw-m3.5735/
Use what the manufacturer recommends for that model.
It isn’t specified in the owners manual and I can get a clear answer from bmw.
I would use any 5w30 synthetic blend.
Look on the oil cap. Sometimes it is written on it.
