Have a truck that doesn’t seem to heat up? A lot of times this problem is caused by worn out thermostats. Update the rear thermostat in your 2001 to 2016 Duramax 6.6L V8 vehicle with this high quality ACDelco replacement.
You can find the rear position thermostat in 2001 to 2016 Duramax 6.6L V8 vehicles towards the fire wall. It's identified by its offset design and has has bleeder valves built in.
This thermostat opens at 180 degrees, allowing coolant to flow to the radiator.