winter motor oil

[jacabean]

would 10w-30 be ok for winter usage ?

[JFP in PA]

Originally Posted by jacabean

would 10w-30 be ok for winter usage ?

No; the M96 needs 40 weight on the high side, summer or winter...........30 weight on the high side is not enough.

Look for Castrol Syntec 5W-40 or 10W-40 (my preference).............

[mikefocke]

Engine Oil Recommendation in my 986 owner's manual yesterday.

I was amazed to see that 10W30 is actually listed in colder (Below 50F/10C) environments. And then contradicted in bold with a "10W40" or higher statement.

I wouldn't and don't use ..W30 but I wanted to interject this little bit of Porsche's contradictory view into the discussion.

You ought to see the viscosity Honda recommends/uses!

[jacabean]

Now that i spent a little time trying to get a better understanding of what the oil numbers really mean , i guess that 5w-40 would be the oil to use year round . the thin 5w for cold start and the thick 40 for normal operating temps. the only thing i question is in january the temps here can stay down below freezing for some time. In those temps does the oil really make it to the "normal" operating temp ?

[Steve Tinker]

The oil gets to its optimum working (hot) temperature only after about 5-6 miles of driving under normal conditions. The overall oil temperature is controlled (up to a point) by the coolant temperature via the oil / water heat exchanger mounted on top of the crankcase.
One way of causing oil contamination is to drive short distances in cold, humid climates at low temps - this causes high water & fuel contamination to the oil.

[Surfncpa]

The dealership put in 0W40 Mobil 1 when they changed my oil. If I understand it all, wouldn't 10W40 be the best choice for Houston?

[Brucelee]

Any name brand 0-40 or 5-40 synthetic should do the trick.