M1 0w40 SM vs SN formula

[Patman]

I can't seem to find it on a search but what were the reasons why people on here preferred the SM formula of M1 0w40 over the new SN formula? M1 is on sale right now at Canadian Tire, and my wife's Jetta was due for an oil change and I managed to get the last 6 bottles of the SM formula. Last year when I changed her oil the SN formula wasn't even here, but now I see it a lot, so I was surprised to find they still had enough SM for one oil change. Is the SN formula thinner? Less PAO? I know her engine likes the SM formula, as it only burned 1L of oil in 15,000km. I know the 2.5L VWs usually consume a lot more than that, I've heard a liter every 4000km isn't all that uncommon.

 

[JHZR2]

Interesting that we consume zero in 5000mi.

I need to stretch her OCI out. We tried castrol 0w-40 made in Germany; not an answer to your question... I'm just surprised at the consumption rate!

 

[Quattro Pete]

Originally Posted By: Patman
Less PAO?

Yup. Sometime around the switch from SM to SN, XOM started using VISOM base stocks (group III) in M1 0w-40. Still, that would not stop me from running it.

 

[domer10]

I just picked up 6 litres from CT today for the M3, it was the SM Formula.

 

[dailydriver]

They dropped the VI a whopping 2 points as well for the SN vs SM versions.

 

[JAG]

I think the MRV and cold cranking viscosities went up but that only matters to those in the frigid extremes. The SN version seems to hold its viscosity better.

 

[Ayrton]

Originally Posted By: Quattro Pete
Originally Posted By: Patman
Less PAO?

Yup. Sometime around the switch from SM to SN, XOM started using VISOM base stocks (group III) in M1 0w-40. Still, that would not stop me from running it.


I think most of SM lifespan was VISOM. The Powerpoint is very old, much older than the switch to SN.

 

[Quattro Pete]

You may be right on that. However, I believe that pour point and MRV parameters took a turn for the worse when SN was launched, and that would point to some change in base oil formulation.

 

[bigjl]

Can only find the SN version in my Costco.

Is £20 more per 5 litres so i don't even look at it outside Costco

 

[Ayrton]

Originally Posted By: Quattro Pete
You may be right on that. However, I believe that pour point and MRV parameters took a turn for the worse when SN was launched, and that would point to some change in base oil formulation.



I agree. They must have reduced PAO or Visom even further around the time of SN debut. There has been a lot of changes.

When the VISOM version first came out (fairly early on in SM lifecycle), its numbers were close to a PAO product.