Do these two oils differ substantially ?

[zray1]

Mobil 1 5w-40 European formula FS /X2

vs

Mobil 1 5w-40 Formula M


The only labeling difference I see is the Formula M meets the 229.5 spec. and the other bottle doesn’t mention it.

How to find out the difference between the 229.3 and 229.5 specifications ??

 

[blufeb95]

They're different oils, the Formula M is closer to a mid-SAPS oil while the FSX2 should be around 1.36% if I remember right even though it's not listed on the datasheet anymore. I doubt anything would be damaged mixing them but mixing them may result in a mixture that no longer meets the stringent requirements of MB 229.5 for extended drain intervals.