if you live in a place that the temp. is below o, then use 5w30, to have better start in cold weather. but if the temp. never goes below o, then use 10w30
does your rpm is fluctuate btw 500rpm and 800rpm when the a/c is on? this is happen when your car is at stop and a/c is on. is this normal? do yall know why it's does that?