The key to maximizing the life of aluminum radiators is not the coolant brand, but the water type. All coolants sold today fully protect aluminum radiators, but distilled water must be part of the packaging. Concentrated coolant creates potential problems because the installer can choose the source of water, which is where many people make big mistakes. Although the coolant contains a package of inhibitors, all sources of water contain a variety of minerals that can be eaten through aluminum. So what is the possible source of water? Let's start with well water, which is usually filled with iron and is very hard. If the well water softens, it contains sodium or salt. Tap water in local municipal water supplies contains varying amounts of calcium, fluorine and chlorine. Therefore, the only way to ensure that the water you use is chemical and mineral-free is to purchase distilled water from your local grocery store. Older copper radiators have made us angry because their attitude towards these minerals is so tolerant. Old timers have difficulty with this water demand because they have used all types of water in the past without any problems. The solution to this water problem is simple, don't buy concentrated coolant. Purchase coolant in premixed form to eliminate any possibility of error. Premixed coolant already contains distilled water and the right ratio to make your cooling system simple. You no longer need to premix the coolant or guess your water ratio. Just pour in and forget about it. I recommend using five years of coolant and changing it every three years to ensure safety. The reason a coolant has a term in life is because of how long the inhibitor package will last. Keep in mind that when determining the condition of the inhibitor package, it is independent of the color of the coolant. When the inhibitor package decays, you are no longer protected by minerals that eat aluminum.