I disagree with a 40 weight, the oil recommendation in the manual states 5w30 for climate temp under 30 degrees and a 10w40 for 30 plus.

I have royal purple 5w30 in mine at the moment for winter (dc2r just clocked 150k), it's done 3000k's so far and hasn't burned much off at all!

So, yeah, chuck it in through the cold months, then put something a bit thicker in for summer

This is unless of course it is burning through the 10w30