Do radiator cooler additives really work and if so--which are the top two?
Some of it is "snake" oil (that doesn't work) and some of it works to some extent. Realize that the best cooling is water. Water has specific heat and cooling.
So water actually cools better than antifreeze. But of course it will corrode things and capitate over time and eat up metal, and it will freeze when it gets cold outside. So you add antifreeze.
Some of those do add a little bit -- a percentage. I've seen tests where they proved that they dissipate like 6-7% better than the regular ones do. But what is 6-7%? It really doesn't mean anything or add much to the performance.
If the car runs okay, run it at a regular 50-50 mix of antifreeze and water and just let it be. And, if you are really into racing and cooling and stuff, then a lot of guys would use those fancy waterless cooler ones that you don't put any water in. You just pour their special antifreeze in. But for normal driving, a 50-50 mix of antifreeze and water is perfectly fine and I wouldn't mess with additives like that.
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