PYB 20W-50 - NOACK 4.9%?

[Falcon_LS]

I was looking for some info on Pennzoil 10w40 conventional and came across the TDS with everything from 5W-20 up to 20W-50.

The 4.9% NOACK caught my attention - given the average NOACK is ~14% for the others, how come it's so low for their 20W-50? Off the top of my head, Liqui Moly's PAO based 10W-60 has a NOACK of 6% and that's a synthetic. What kind of base oil/add pack are they using in their 20W-50?

 

[aquariuscsm]

Originally Posted By: Falcon_LS
I was looking for some info on Pennzoil 10w40 conventional and came across the TDS with everything from 5W-20 up to 20W-50.

The 4.9% NOACK caught my attention - given the average NOACK is ~14% for the others, how come it's so low for their 20W-50? Off the top of my head, Liqui Moly's PAO based 10W-60 has a NOACK of 6% and that's a synthetic. What kind of base oil/add pack are they using in their 20W-50?


I was looking at pds sheets recently and saw Maxlife 20W50 has a super low NOACK like that too. The 20W50 was the only Maxlife that had that super low number.

 

[Gokhan]

Of course, 20W-xx uses very thick base oil -- little evaporation -- with a very high CCS. NOACK is inversely proportional to the CCS viscosity -- so, this is entirely normal and typical for a conventional Group II 20W-xx.

Most conventional Group II 15w40 HDEOs have NOACK less than 10%.

 

[Garak]

Originally Posted By: Falcon_LS
I was looking for some info on Pennzoil 10w40 conventional and came across the TDS with everything from 5W-20 up to 20W-50.

You'll usually find some very low Noack values in 20w-50 conventionals, even in 10w30 conventionals.

 

[Oil Changer]

This sudden fascination (Or should I say fear?) of NOACK that propagates throughout this forum is meaningless to most of the membership. I guess we have Pennzoil and their fluid PDS for that.

I wonder how many oils-of-the-month there has been on BITOG that had higher percentages and no one said a word until that Ultra PDS came out?

 

[steveh]

Originally Posted By: Oil Changer
This sudden fascination (Or should I say fear?) of NOACK that propagates throughout this forum is meaningless to most of the membership. I guess we have Pennzoil and their fluid PDS for that.

I wonder how many oils-of-the-month there has been on BITOG that had higher percentages and no one said a word until that Ultra PDS came out?
Just like the high VI fascination.

 

[Shannow]

Except NOACK does have a reason to be attentive., whereas VI doesn't give you any data unless you know something else about the oil (KV40 or KV100).

Originally Posted By: Oil Changer
This sudden fascination (Or should I say fear?) of NOACK that propagates throughout this forum is meaningless to most of the membership.


Why do you say that it's meaningless ?

 

[Gokhan]

NOACK volatility when combined with CCS viscosity is one of the main indicators of base-oil quality.

What the OP didn't know was that you can't consider NOACK alone when you judge base-oil quality. You need to consider it along with CCS, as obviously thicker oils will always have lower NOACK than thinner oils within a given base-oil type/quality grade (Group I/II/III/IV/V/GTL).