I would be more inclined to look at hoses and hose clamps. Clamps back off, hoses get holes in them. Thermostats, however, do get stuck closed causing coolant to boil over. I have included a couple of links down below for you to go to.
I have also included for you in the diagrams down below an exploded view of your vehicle's cooling system, as well as coolant type ans capacity and torque values for any parts that might be removed and then reinstalled.Please go through these guides and get back to us with what you are able to find out.
Images (Click to enlarge)
Tuesday, April 30th, 2019 AT 9:33 AM