Radiator overflow tank

ir3333 said

You don't need an overflow tank... just don't fill your rad to the top.
The overflow tank will give you a couple of quarts more coolant.

Click to expand...

I used to obsess with filling to the top. I was always filling and watching the overflow level increase.
I finally listened and accepted the advice: "Your radiator will find it's own level"!
The radiator levels out at the top of the upper hose, so there is always an air gap to the cap.
My overflow stays at the same level.