I used Lucas Oil treatment for the first time a few months ago. It makes the oil look like honey. I'm not referring to the color, just the way it acts - sorta stringy if you touch the dipstick with your finger and pull it of, as if it has more "grab." I've always been suspect of oil additives, but decided to try it since I have yet to hear anything bad about it. I ended up putting it in my lawn equipment too, and some 90wt in the differential.
You might consider trying some of this to see if it helps. Run your typical grade/weight, but substitute one qt of the Lucas for your oil.
Bill
