Moving back to 5w-20

[LotI]

Originally Posted By: Shannow
Originally Posted By: HTSS_TR
Originally Posted By: wemay
0w20 is 'better' than 5w20? Really?

To achieve the 0W rating it has better base stock (more group IV PAO) than 5W.

Whenever I'm buying any synthetic brand I always pick 0W if it's the same or not much higher price than 5W.


Not quite sure that I agree with your philosophy...if my vehicle called for a 20, and my climate was such that a 5W was appropriate (I don't NEED 0W), I'd take the 5W every time.

Look at these for an e.g.
http://www.pennzoil.com/wp-content/uploads/2014/04/Pennzoil-Ultra-Platinum-0W-20-SN-GF-5-en-TDS.pdf
http://www.pennzoil.com/wp-content/uploads/2014/04/Pennzoil-Ultra-Platinum-5W-20-SN-GF-5-en-TDS.pdf

the 0W has quite a lot higher NOACK, and it's density is a little lower, indicating that the 0W uses a somewhat lighter basestock, and more VII (of any description, good, bad, or otherwise).

Likely less deposits, better viscosity retention with the 5W.


But, if you look at the same company's (SOPUS) offering in the QSUD line, the 0W-20 has lower NOACK.
11.3% vs. 12.5% and a higher HTHS vis. indicating better base stocks.

QSUD

 

[Shannow]

Thanks, I just used the first that I found with a common data sheet....
Lower density and flashpoint for the 0W20, meaning lower viscosity basestock, and probably more VIIs too...lower NOACK interesting considering...

But plugging into A Harman's shear calculation technique, both are quite close to each other, making shear stability at least likely a wash...either would be good for an application needing a 20.