I've got an '00 Si with a JDM SiR motor. I'm running Mobile One 10-W30 oil, and was looking at 15-W50, mobile one's performance oil. I live in WI and it will be driven in the winter. Would this be a good motor oil for the summer? I'm thinking winter would not be such a good idea.

 

There have been many topics discussing motor oil. Lots of information in the archives, so try searching

 

15W 50 is not for imports, and where you live you should be runnin 5W 30. You only kick it up to 10w 30 if you live in hotter places, but even in hotter places people still run 5W 30.

 

5W 30 will be just fine for your car

 

I run 10w30 also. I wouldnt run 15w50 is not even close to what you want. youll probably have a noticably harder time starting the car in winter if you were to run it. also even after warmed up its going to be way to thick. 5w30 or 10w30 is the way to be.

 

10w30 in the Summer.
5w30 in the Winter.