So I was reading some here via a Google search about private label brands. Has anyone ran say Super Tech, NAPA etc and noticed if you look down the fill hole any black stuff, varnish or bad stuff there? Seems the more I read on here people think that oils that are not PYB, QSGB, Smittys super S, MS5K then these "private label oils" don't have a great add pack. Thank you folks in advance