More than 10 years ago, I met a lady that worked for Honeywell. Honeywell owned Prestone at the time, maybe they still do. Anyway, they also made the Walmart supertech antifreeze at that time. She said that the Prestone was superior, that the Walmart store brand did not contain the same anti-corrosion additives. I'm not sure if it was the formula that was different or the concentration. Anyway, that was a long time ago and I cannot say if it still holds true.