Outside the debate of syn vs non-syn, and since yall know oils and their grades... Who makes a synthetic 15w40 besides Amsoil.
And mixing oil brands and weights isn't a issue right? By that I mean the truck leaves a bit of oil behind each change. And I'd like to run 5w40 in the winter since it starts much easier and 15w40 in the summer
And mixing oil brands and weights isn't a issue right? By that I mean the truck leaves a bit of oil behind each change. And I'd like to run 5w40 in the winter since it starts much easier and 15w40 in the summer