I went here to get some service done. They did several things including change of my thermostat. I normally like Firestone and prefer to go to them. I was disappointed that they charged me a diagnostic fee and did not credit that fee towards my expensive repair.
Fast forward to a later date, my car overheats again. I take it to another Firestone, and they tell me (and show me) that the thermostat gasket was installed incorrectly.
No big harm, I don't think there was any engine damage. Firestone in Glendale, Ca fixed the issue under warranty.