When up to temp, my coolant is at max. When it's cold, there is room for a touch more. Add more when cold to get to Max line?

 

No. Sounds like it's just right. Hot or cold best not to exceed the max.

 

Ok, thanks!

 

When the coolant is hot it expands, when it is cold it condenses. This is why there is a Max and a Min line on the expansion tanks. It allows the coolant to go someplace when it is hot and not just dump on the ground. Your system sound like it is working as designed.

 

Thanks! About to setoff for a rather long trip so checking everything out.