What viscosity of motor oil to use in winter?

["Serge Maillet" <serge.maillet@xxxxxxxxxxxx>]

G'day fellow bimmers!

Quick and simple question. I have an E36 with 60k miles on it. I'm using Mobil
1 Synthetic motor oil but I'm not sure which viscosity I should be using. My
last oil change, I used 5w30 and I live in a cold climate in Eastern Canada
(Ontario) so the temps sometimes go 15 degrees or so...   what's the
recommended viscosity by BMW in this climate? Unfortunately I do not have an
owners manual, otherwise I would look it up myself. I'm due for another oil
change this Friday and I'm thinking about using either 10w30 or 15w50. Any
recommendations or opinions would be greatly appreciated.

PS - I change my oil every 3500 miles with Synthetic oil. Is this overkill? I
noticed that the oil change notification lights only come on the "red" every 3
oil changes I do. My mileage is also mostly country/highway driving.

Thanks again!

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