Coolant overflow tank/reservoir

[4u33er]

My coolant is low on the overflow tank. Even when cold it does not reach the cold line on the tank.But my question is the overflow tank one way or does it recirculate back to the radiator?I ask because I want to add water wetter and wondering if through expansion tank it will all mix eventually.

 

[Dennis]

Fill your reservoir to the Cold line on the tank..Just add the Wetter stuff to the tank..it will mix..the tank coolant is always circulating back and forth to the coolant system..may take about a week of driving to completely get a full exchange, but it will.