Flushing Coolant Questions
 

I am wanting to flush my coolant in my 2004 Silverado. I do not have a machine and am wanting to do it with a garden hose. My plans is to drain the old coolant and refill with water from a water hose and run until the thermostat opens and then drain. I'm gonna do this 2 or 3 times. When i get done and put good coolant back in how do get out all the water from the garden hose? I know there has to be a 50/50 mix with Distilled water and coolant. So How am suppose to get the water hose water out that is left in the engine? Thanks for your help!

Thats old fashion, but works. I'd suggest pull the tstat, run with radiator flush, follow directions on flush, replace tstat when done. I should have said on "replace tstat", replace with new one

add full strength coolant, run it to mix. cool and check the concentration. Too weak; drain and add conc coolant. Too strong drain and add h20.

The Perfect Solution
 

I think that your intent is to get as precise (50/50) mix as possible.

And after cleaning, flushing (several times is preferable) and draining, there is only one way to get a perfect dilution in there, considering that there will be pockets of (hopefully) clean water, unavoidably remaining in the System.

You must look up the capacity of your system.
Purchase 1/2 of that volume in a good quality/appropriate Antifreeze.
Pour that into your radiator (full strength), and fill the rest of the system with water.

You should buy a little more Antifreeze than the 1/2 volume, where you can premix the Reservoir content, initially fill and subsequently add therein as necessary. You'll probably have a "burp" or two as the system warms up and cools a few times. Once you see that there is a transfer of Coolant from your Reservoir to the System (and back) when it warms, do not remove the Radiator Cap again. Just make sure that you do not allow the Reservoir to run dry of Pre-Mixed Coolant.

Note 1:
Some Cooling Systems, can really be stubborn when it comes to draining completely. Frequently, there are rather large volumes of water remaining after the final draining. Using the above method to achieve the 50/50 solution is much more reliable, than using a Pre-Mixed Coolant, because of these unknown volumes of water. However, having a Pre-Mixed Coolant for the initial filling the Reservoir or subsequent "top-offs" is quite acceptable.

Note 2:
Periodic testing of the Coolant proportion in your system, can be rather important, should you frequently operate your vehicle in extremely hot (ambient) conditions. Etheline Glycol has a boiling point of 387°F, and as you know, water boils at 212°F. The additional increased boiling point of water at approximately 3°F/1Lb pressure, often times is insufficient to retain the water in the system, during a sudden stop from high speed, or shutting the engine down without allowing the temperature to drop. Subsequently, when these occasional "boils" occur, it is usually the water component of the Coolant, which is converted to steam, and evacuated out through the Reservoir. Repeated occurrences of this condition, will reduce the proportion of Water/Antifreeze, and "richen" the mixture, causing there to be a higher content of Antifreeze in the system, than intended.
Often times, this can reduce the efficiency of the System to dispel heat.