0w-30, 5w-30, and 10w-30 are all 30 wt oils at 212F. The 0w, 5w, and 10w only refers to the pumpability at 0 degrees. When your engine is warmed up, 0w-30 is still a 30 wt regardless of ambient temps. It will work the same in Florida as it would in Alaska.quote:
Originally posted by 98RegalGS:
Could I use GC 0w-30 even though my engine specs for 10w-30? A 0w is a bit thinner, correct? Couldnt I get blowby running that oil?
Or maybe IM misunderstanding the numbers.
The german version of Castrol Syntec 0w-30 is significantly thicker than Mobil1 0w-30 and almost as thick as Mobil1 0w-40
Look around here a bit and you'll understand that some Xw-30's are closer to 20 wt oils while others are almost 40 wt oils. GC is one of those that is almost a 40 wt.