I noticed this last few days that after I turned my car off,both the hoses starting to collapsing down until it is almost flat. I could hear the coolant draining back somewhere(The radiator or the engine )? After it cool down a bit the hose will bounce back to its old shape. I don't see a leak anywhere and the temp gauge is showing a little on the cool side ( 140'-160'F ) . I am running a 180'F thermostat.
What could be happening ?
What could be happening ?