Originally Posted by TheIceStormof06
Originally Posted by motech
Will do. Although there is also the new VW branded oil- I believe also made by Mobil- in a 0w30 weight that hits 504/507. Part #GE550301QDSP. I may run that instead and do the same test.
I think your engine was originally spec'd for 0w-40, 5w-40. I'd stick with 5W-30. Your in S. Carolina. 0w weight isn't necessary. Plus I've always heard the larger the spread means more Viscocity improvers and additives? Also, I've always though the HTHS is higher on 5W-40/5w-30 than the correlating 0W-XX oils. If your going down into the 30s that's essentially 1 grade lower. PLUS, over the OCI, the 5w is more likely to remain in grade vs. 0W.
W40 does not have anything to do with specification, HTHS does. Also, HTHS is not dependent on 0W. Base stock are relevant in that case.
For example:
Castrol Edge 5W40: KV100: 14.2, HTHS: 3.7
Castrol Edge 0W40: KV:100 13.1, HTHS: 3.7
The difference is that 0W40 has healthy dosage of PAO, unlike 5W40, and bcs. of that also lower Noack. If base stock was same, 5W40 would have lower Noack. However, 0W40 and 0W30 oil usually have more PAO or Esters.
Also, going into W30 is NOT a grade lower. Grade is spread.
W30: 9.5-12.5cst
W40: 12.5-16.3cst
Most Euro oils are light W40, heavy W30.
Castrol Edge 0W40: 13.1cst
Castrol Edge 0W30: 12.2cst.