Coolant issue on 2001 N/A Bonneville

[Tannmann36]

I've started to notice that my coolant drains slowly for about a month now and not sure where it's going, also it has started to become very murky and almost muddy looking. I was thinking it was a gasket but I changed the oil about 2 weeks after this started and it looked fine and still does. Also I checked for air bubbles indicating exhaust gases and saw nothing. I haven't tested it to see if there really are exhaust gases or not and probably will soon though. There are no visible leaks that I know of and the temp gauge doesn't ever get super high. Side note it does seem to get really hot under the hood but not sure if that's normal or not and it's been like that since I got it. And tips or suggestions would be appreciated.

[95naSTA]

The two common internal coolant leaks are:
-From the EGR melting the upper intake manifold next to the coolant passages that run to the throttle body. Dorman has a gasket kit for the UIM with an updated 'stove pipe' that's smaller in diameter where it goes through the UIM. You'll need to replace the UIM if it's melted through. Alternatively, you can fill the UIM coolant ports to the throttle body with JB weld which will block coolant. This coolant circuit is meant to prevent throttle body plate icing. I ran this way for years without issue and I've never seen anyone else have an issue with it either.
-The lower intake manifold gaskets failing. The LIM gaskets were revised to aluminum vs plastic in the mid-00s and they last much longer.