AC Delco thermostats are made in the United States by General Motors at the ACDelco plant located in Grand Rapids, Michigan. The facility is capable of assembling and testing millions of thermostats per year, ensuring that quality and reliability remain high for all products manufactured there. All ACDelco parts undergo rigorous testing to ensure that they meet or exceed OE specifications for safety and performance. Additionally, most ACDelco parts have a limited lifetime warranty which provides peace-of-mind protection for vehicle owners who choose them as part of their repair solution. So when you need a reliable thermostat replacement, be sure to trust an ACDelco product from Grand Rapids – no other brand can deliver the same level of quality and dependability!