Mobil 1 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 Mobil 1 0w40 over the new SN formula? Mobil 1 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 Mobil 1 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 Mobil 1 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.