What is this Mobil 1 0W-40 FS X2?

Joined
Feb 9, 2021
Messages
71
What is this oil I have never seen before? Is there any difference between this and the Mobil 1 0w-40 I have been running. Was going to buy the Mobil 1 0W-40 FS for its higher HTFS specs since this car sees 5-8 track days a year and its a VQ35HR so its super hard on oil (yes I do have a bit dual pass oil cooler so temps never go above 265F).
 
What is this oil I have never seen before? Is there any difference between this and the Mobil 1 0w-40 I have been running. Was going to buy the Mobil 1 0W-40 FS for its higher HTFS specs since this car sees 5-8 track days a year and its a VQ35HR so its super hard on oil (yes I do have a bit dual pass oil cooler so temps never go above 265F).
Look closely, that's M1 FS X2 5w-40.

 
It was called FS X2 for a while, but the same SKU was changed to just FS once they added MB229.5 approval, I'd suspect if you order it you might receive the newer FS version, apparently the oil is the same, just the FSX2 only claimed MB229.3 not MB229.5 and MB229.3
 
What is this oil I have never seen before? Is there any difference between this and the Mobil 1 0w-40 I have been running. Was going to buy the Mobil 1 0W-40 FS for its higher HTFS specs since this car sees 5-8 track days a year and its a VQ35HR so its super hard on oil (yes I do have a bit dual pass oil cooler so temps never go above 265F).
Try Castrol Edge 0W40 also. It has higher HTHS than M1 0W40.
With those oil temperatures you are good with any Euro spec. XW40 oil in this category.
 
Try Castrol Edge 0W40 also. It has higher HTHS than M1 0W40.
With those oil temperatures you are good with any Euro spec. XW40 oil in this category.
I almost went with the castrol but someone steered me toward the M1 as it has esters which this engine is supposed to have to keep the valve train from being noisy.
 
I almost went with the castrol but someone steered me toward the M1 as it has esters which this engine is supposed to have to keep the valve train from being noisy.
Actually in all my vehicles Castrol 0W40 or 0W30 were always smoother. That does not mean anything, but M1 was always known as "noisy" oil.
 
What is this oil I have never seen before? Is there any difference between this and the Mobil 1 0w-40 I have been running. Was going to buy the Mobil 1 0W-40 FS for its higher HTFS specs since this car sees 5-8 track days a year and its a VQ35HR so its super hard on oil (yes I do have a bit dual pass oil cooler so temps never go above 265F).
FS stands for full-SAPS as usual with M1 oils.

It is rebranded now as FS 5W-40 instead of FS X2 0W-40, with the same formula.

It has outdated certifications. A3/B3 no longer exists. It doesn't have A3/B4.

Do not use this oil, which is of mostly petroleum-derived Group III. Use M1 FS 0W-40 instead, which is of mostly GTL. M1 FS 0W-40 has current certifications, and the base oil is as thick and Noack is as low or perhaps even thicker and lower. It is a much better oil in every aspect than this outdated one.
 
FS stands for full-SAPS as usual with M1 oils.

It is rebranded now as FS 5W-40 instead of FS X2 0W-40, with the same formula.

It has outdated certifications. A3/B3 no longer exists. It doesn't have A3/B4.

Do not use this oil, which is of mostly petroleum-derived Group III. Use M1 FS 0W-40 instead, which is of mostly GTL. M1 FS 0W-40 has current certifications, and the base oil is as thick and Noack is as low or perhaps even thicker and lower. It is a much better oil in every aspect than this outdated one.
They have updated the 0w-40 and kicked out gtl, and replaced gtl with pao
 
They have updated the 0w-40 and kicked out gtl, and replaced gtl with pao
I checked the MSDS for M1 FS 0W-40 today. It is still 10–20% PAO and 50–60% GTL. From the FTIR data, add about 5–7% POE on that. Note that the additive package and VII make up the remaining 20–25% percent.

It is hard for them to achieve the SAE 0W MRV and CCS specs along with the 9% Noack spec for a Euro 0W-40 without any PAO, as the SAE 0W-40 requires quiet a bit VII, which increases the MRV; so, you're trying to keep the Noack low with a base oil thin enough for the MRV and CCS still to be in target. The PAO comes to the rescue.
 
Last edited:
I checked the MSDS for M1 FS 0W-40 today. It is still 10–20% PAO and 50–60% GTL. From the FTIR data, add about 5–7% POE on that. Note that the additive package and VII make up the remaining 20–25% percent.

It is hard for them to achieve the SAE 0W MRV and CCS specs along with the 9% Noack spec for a Euro 0W-40 without any PAO, as the SAE 0W-40 requires quiet a bit VII, which increases the MRV; so, you're trying to keep the Noack low with a base oil thin enough for the MRV and CCS still to be in target. The PAO comes to the rescue.
Check the thread in the Euro section, there are new, updated, European MSDS sheets, whereas the US one is still from 2019.
 
FS stands for full-SAPS as usual with M1 oils.

It is rebranded now as FS 5W-40 instead of FS X2 0W-40, with the same formula.

It has outdated certifications. A3/B3 no longer exists. It doesn't have A3/B4.

Do not use this oil, which is of mostly petroleum-derived Group III. Use M1 FS 0W-40 instead, which is of mostly GTL. M1 FS 0W-40 has current certifications, and the base oil is as thick and Noack is as low or perhaps even thicker and lower. It is a much better oil in every aspect than this outdated one.
That is what I ordered and plan to run for the next year. I change the oil every spring when the car comes out of storage, every fourth track day, and again right when the car goes into storage. I do not start it while it's stored.
 
My solid tappet valves are noisier with Castrol (of any viscosity) than Mobil 1.
0W30/40? Bcs. those are different oils than any other Castrol. I had lifter noise always with Castrol 5W40.
IMO noisier oils or not, it doesn’t matter. I use M1 although they do have bit of noisier operation in my Toyota or VW for example. In BMW inline 6 quiets down everything.
 
0W30/40? Bcs. those are different oils than any other Castrol. I had lifter noise always with Castrol 5W40.
IMO noisier oils or not, it doesn’t matter. I use M1 although they do have bit of noisier operation in my Toyota or VW for example. In BMW inline 6 quiets down everything.
Yes 0w40 A3/B4 and their SP rated 10w40. I don't think it matters either and would not hesitate to use it if the price is right, but it's interesting nonetheless.
 
Back
Top