Originally Posted by bill_de
Well, they mean what they say. Don't use "Straight 20 weight" or "Straight 10 weight" etc. The spec calls for a multi-weight, like 5w20. They are not specifying that you use a synthetic. Nothing wrong with doing so if it makes you happy. But don't use it because you misunderstood the owners manual.
I'm guessing (somebody correct me if I'm wrong) they say straight mineral oil because all synthetic sold over the counter is multi-weight.
Incorrect, "straight mineral oil" refers to what some call "dino oil" the hemi was designed to run with a synthetic blend at MINIMUM. So I believe that's what is referring to. You can also get a single weight synthetic for various purposes. It mentions elsewhere only use 5w20 weight which is a completely different reference.
Not trying to ruffle feathers, since I'm new to the forum.
Also a member of "ls1tech".
Look forward to learning more about my WK2 from you guys though!!