I have a '96 328CI and the temp. display for heat and AC displays in "C" vs. "F". How do I change it to display in "F" (fahrenheit)? Also my manual is very confusing regarding oil requirements. I want to use synthetic and I don't think the manuals choice of 15w-40 sounds right. It also shows 5w-30 but it doesn't protect above 65 degrees "F" and the
15w-40 should not be used below 14 degrees "F".Dave