coolant flush

Is the proper way to remove the thermostat?
Can I drain the radiator, fill with distilled and run it...repeat till clean. But at that point the engine is full of water...and winter is coming.

Can I remove the return line coming from the heater core and stick a hose in the radiator and run it till clean water comes out of the return? But again I'm left with all water in the system

Can I add G-05 to (what I assume is) factory fluid?

I would like to get rid of all old fluid and add new, but I guess I would settle for a radiator drain and fill if the flush is too involved

What year is the truck? If it's a newer one with the HOAT fluid your stuck with purple coolant that's like $50 a gallon and it's good for 100k before needing servicing.

To do a Tstat swap, remove the hose and pinch the hose to keep fluid loss to a min, try to catch what you can. And reuse but u will still need a little.

Can't run straight water, esp if you get anywhere near 32* ambient or your going to destroy the motor. Straight water even in old school Motors needs a lubricant and corrosion inhibitors.

You haven't posted any reasons, or issues for fluid flush and Tstat change. Is it a mileage thing? Are you doing it bc u feel like it's necessary? Most of the fluids in these trucks have extended service intervals, trannies, coolant and even oil can go 10k with good oil and good filter. Don't do things just to do them. Basically more info is needed to make a better response on our end. And this should be in the engine tech section and not DIY. This section is for showing people how to do something themselves... not asking how to do something.

Judging by what you've stated thus far I think you should have someone do it if you feel like it needs replacement.

Don't use raw water from a hose. You only want to introduce distilled water with no mineral content. I personally wouldn't use a citric acid flush. Citric acid is an organic acid chelant so it will pick-up iron but in my opinion just flushing with distilled water and then adding new Mopar coolant is the right thing to do because you never get it all out of the vehicle. I'd fill with distilled... drian.... fill with distilled......drain....fill with distilled....drain. After 3-4 times you will be down to raw water. I use conductivity meter to measure the distilled water vs. what I'm draining to confirm the degree of flush.

Do it slightly ahead of the regular schedule.