I disagree....bubbles will affect your tranny's performance and buildup heat. And eventually burn out your tranny. It is just like the power steering pump. You dont want to have air bubbles. My tranny guy puts an additive in all his work. I use royal purple in my tranny and power steering pump. If you ever read the label on royal purple, they are concerned about bubbles and breakdown in oils and additives. Its expensive stuff but they've proven their products.