Bought a 55 G drum of the synthetic oil in 2008. It is laying on its side on a stand, and I take 5 qts out every 3-4 months. I have a valve installed and crack open the top to vent it and drain out what I need. After searching the shelf life issue, I am starting to worry that maybe I should be rolling it around the floor before I drain some out. Then someone else says to ship it to them to use, so from a technical standpoint, should I be rolling and sloshing it around before draining out my 5 qts or invite the neighbors over for an oil change. Any comments?