Any Chevy mechanics here?

[crays]

I've got a 2014 Silverado that I think is needing a new thermostat. Temp gauge is running cooler than normal and fluctuating, and heater isn't like it used to be. Looked up the process on YouTube and actually changing it ain't no thang, but then the dude hooked up a computer and had to change a buncha shit, and that's outta my league.

Any wrenches here? Close to Parker? Maybe trade for deprimed and wet polished brass?

Captain Obvious here, but you have checked the coolant level haven't you? Sounds a lot like low coolant symptoms.