Oil consumption!

That depends on the oil you use. I use Amsoil 10-30 Signature. The difference in flow between the 10-30 and 5-30 is only 3 degrees at something like -40. There really is no difference. Full synthetics are far superior in frigid temps. I've run this 10-30 down to -20 so far and it does turn over "slightly" slower than the 5-30 but not by much. I just added a pan heater and it's the same.

 

I've since gone to 5W-40 diesel engine oil. Engine clatter has reduced and the difference in viscosity when warm is insignificant compared to 5W-40 or 0W-40.