mixing 5w30 SM and 15w40 CI-4/SL

[akela]

Is it okay to mix 5w30 SM and 15w40 CI-4/SL ?? Both SuperTech.

I have 3 quarts of each of these oils, and just want to use up this "stash" at the next oil change. I know that mixing oils from the same group is allright, but these two belong to different categories, SM and SL, which causes little doubts.

The engine is GM 3.1, if it makes difference. The winters are mild here in Vancouver.

 

[addyguy]

Sure - will work great!

You can mix any oil with another oil w/o issue these days.....

 

[chubbs1]

Go for it, it will change the viscosities little.

 

[akela]

Thanks for the replies. Will go for it.