SM / CF vs. SM Question

[dave munson]

Most of the oil I see is rated SM. Some of the premium stuff is SM/CF (Mobile 1, some other full synthetic and a very very few non-syn PCMO. I believe that CF is a diesel rating and SM is the latest gas engine rating.

Anyway, would not oil rated "SM/CF" be a ---better--- oil than just SM oil for a gas engine?

Any difference between a gas SM/CF or a diesel CF/SL (assuming that SM / SL is both OK)?

 

[bruce381]

same stuff

 

[bruce381]

sorry better answer is that a dual use oil will be depending on rating "better" than just say a SM. A CJ-4/SM the diesel spec in front would be better than JUST a SM alone.

But a SM/CF, gas spec in front will be about the same I do not think I explained this very well tho.
bruce
bruce

 

[bruce381]

the first spec as in SM or CJ-4 when in the front is what the oil is primarily recomended for the second spec is normally "secondary" to the sale/use of the oil.

 

[Ramblin Fever]

You explained it quite well bruce! Very understanding.