Where is the thermostat located on a 2003 Chevy Trailblazer straight 6?
The thermostat comes in a housing that bolts directly to the motor, and is located on the passenger side of the motor, about 1/2 way from the top, & towards the front of the engine. To remove/replace it you need a socket wrench & a 3 to 6 inch extension. There is a small part directly above it that needs to be removed first & only has 2 bolts in it. This is where the thermostat is located on the trailblazer for years 2002 to 2004.