Where is the thermostat located?

Hi,

You need to remove the intake manifold to access it. To get you started, here is a link that shows in general how it's done:

https://www.2carpros.com/articles/replace-thermostat

If you look at the attachments below, they provide the directions specific to your vehicle for thermostat replacement. Also, I included the bleeding procedures. Make sure not to mix the original dex-cool coolant from GM with other types unless it is a universal type indicating it can be used with Dex-cool. This is very important.

The only way to replace the coolant with a different type is to completely remove the old coolant from the entire system, flush it, and then install something different.

Let me know if this helps or if you have other questions.

Take care,

Joe

See pics below.