I noticed the other day that when I turn my car off I can hear a gurgling noise from under the hood. Is this normal? Just coolant or oil settling?

I'd pop the hood and check that out. Make sure the level is up at the right level etc. Maybe ask the local plase to pressure test the rad cap.

Agreed, that is how I would describe the sound of a car boiling over. Mine did that until I noticed the gasket was coming apart on the radiator cap.

So, when I park it just open the hood and look for leaks? Maybe (hopefully) just the rad cap?

Confirm the noise is the car boiling over, then after it cools down, I would look at the cap. If that is fine, you will probably want to have the cooling system pressure tested, along with the cap. Cheap insurance is to just replace the radiator cap however, unless you have reason not to.

Unless he is running near straight water, which I have done before, will produce a gurgling noise because its close to its boiling point(if not beyond). If so, good chance that its just blowing back into the overflow tank.

I haven't been having any problems. It seems to be running normal temp, unless my thermometer is broke. The tank is a bit below the line though.

Also it should be about 5050. I flushed and refilled it about a year And a half ago.

Remove the radiator cap, when cold. Can you see the fluid? Or do you see the radiator core? Add fluid if it'* low.

If you want easy, the 50/50 But if you want to save a little money, then buy full strength as well as a gallon of distilled water and mix your own. Be sure to get the correct coolant. If you get any color, your safe no mater what you have in the radiator.

I did that. I believe it was the color of green Hawaiian punch. I remember thinking it was a bad idea to store a toxic liquid in a jug in a drink jug of the same color fluid.