I think you should ask the serv mgr that question. I asked and was told it was full synthetic and that it was 0-20 wt. I have the 5.3 , that may be different than yours. I also know that they also have mobil 1 as an option.
Dexos if you dont ask for anything else.
Your customer service representative should have informed you of all of that
Call and ask the service center.
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