Looks like your engine fan is very lazy.

 

I know I sound like a broken record on this, but the bleeding issues and high temps are related to the factory thermostat/flow system. Go to the bypass stat and your issues will go away. Don't believe me, do a $5 test. Buy a hose repair kit at advance and put a bushing in place of the factory stat, put the top radiator hose directly to the manifold outlet. Your problems will be magically gone. I could be wrong however, I've only had 12 D2's.

 

Hey Extinct - I hear ya but how come some of these work with the factory set up? I am all for doing performance mods but I also don't want to mask the real cause of the issue...

 

Yep - I am thinking it is time to convert to electric.

 

Do the $5 test and you can easily see if it is a bad fan clutch, plugged radiator, or the thermostat. The problem with the factory thermostats is it can fail in two different modes. Mode 1 it does not open and engine overheats quickly, mode two it allows the coolant to bypass the radiator and it overheats slowly. With the bypass stat you eliminate mode 2 because the bypass hose is gone and the Chevy stats are more reliable with respect to mode 1.

 

Bleeding has not resolved my issues but there was significant air in the system.

As much as I would love to convert to electric, it’s more than I want to take on at this time. I ordered the Hayden 6352 off rockauto and will swap it out hopefully this weekend. Looks fairly straightforward. Stay tuned.

 

Try parking it on a hill, get that front end up.

I dont do anything but park on a hill, let it run, open that bleeder. I also squeeze my hoses.

New parts always help.

Green FRESH coolant. Coolant does go bad.

 

If there was air in the system its unlikely you got it all out in 1 day.. check it 3 days in a row and you might be surprised

 

I think the 2004 has an integrated fan and clutch so I don't think the HD clutch is plug and play but I am also interested in this upgrade so please let me know how it goes.

 

I have been topping off for the past couple of days. Still no change. Going to replace the fan tomorrow. I will pull the stat and test it as well.