Where do you find the thermostat in a 2004 Chevy S-10?

The thermostat in a 2004 Chevy S-10 is located under the intake manifold, at the back of the engine. It's not easily accessible and requires removing the intake manifold to replace it. This is a more involved job than simply replacing a thermostat in many other vehicles. You'll likely need some mechanical skills and specialized tools.