Hi folks. I am sorry if this is a re-thread, but I have searched hi and low on this forum for some sort an antifreeze change narrative, but unfortunately, I haven't had any success... So, I thought I'd just ask...

As background, I bought my srt three weeks ago. It has 16k florida miles on it and is in really beautiful condition. Being an auto geek and wanting to start anew, I have changed out the oil (mobil 1 0w-40 and mann filter), the 2 air filters (NAPA Gold 6875/OEM Mann), and the cabin air filter (i produced a forum narrative with pictures of this procedure in case you're interested).

Next up was an antifreeze change, so I went out and bought all the necessary goodies, to include the Zerex G05 and distilled water. Now, I've changed out antifreeze countless times over the past 40+ years in many different cars, but I still completely read the chapter 7 procedure on changing it out, and I also read everything I could on the Mecedes Benz forum about changing it (there are several good narratives).

Thinking myself adequately prepared to do a simple task, I attempted to change the antifreeze out yesterday, and much to my surprise, I didn't meet with much success. Here's what happened:

As you may know, Chapter 7 says to leave the cap on and open the under radiator valve. So, I opened the valve and for several minutes nothing at all happened. I then removed the cap and the antifreeze started to immediately flow. After about 5 minutes of good flow it started to just trickle a little, but after about 2 minutes it then began to flow again at a good rate for a couple of minutes, and then I just let it drip out for about 10 minutes. For what it is worth, what happened above is exactly what happens when I change the antifreeze on my wife's e320 (same basic engine).

Being a stickler, I then filtered the old antifreeze thru a coffee filter into a container with accurate volume indicators. I was very happy to see that the antifreeze looked clean, fresh, and almost new, and that there was absolutely no debris of any kind found in the filter (I knew the previous owner so I knew that it was the original MB factory antifreeze). So, so far so good..

I now took note of how much fluid I had collected, and was somewhat puzzled to see that I had only collected 8.1 quarts total. On page 243 of the Crossfire owners manual it says that the cooling system holds 11.8 quarts total, but the SRT6 obviously holds 15.3 quarts, according to several sources. So, I had only collected just a little over 1/2 of the total coolant, which concerned me.

I now refilled the cooling sytem with distilled water, left the cap off, started the car, and watched the temp gauge slowly start to rise. When just sitting in the driveway at idle I have noted in the past that my temp gauge needle typically sits just below middle, or 4th tick (there are 7 ticks total). The needle rose to this very same position and I checked the coolant reservoir fluid and it was cold. I then reved the engine up and watched the needle climb to slightly over the middle tick, and then watched it rapidly plunge back down to its original position. I attributed this to the thermostat opening, and when I check the reservoir again I noted that the fluid was now warm. I then shut the car off.

After the engine had cooled I then repeated the steps above and was only able to get 8.1 quarts out again, albeit the coolant color was obviously not nearly as dark this time around. I then refilled the system with distilled water and pulled the car into the garage for the night.

Well, does any or all of this ring a bell with any of you who have changed out their antifreeze before? Am I doing something blatantly wrong which might account for my only getting 8.1 quarts out each time? Given my reading, I'm pretty certain that most of the fluid that I'm not getting out is probably trapped in the intercooler system (pump plus IC radiator, etc), and that I probably just need to take the car out for a good supercharger run to get it all mixed with with the distilled water, right? And then drain it again and do the same supercharger run again? My thinking is that since I am replacing the original MB antifreeze with the Zerex G05 MB certified coolant, that I should just do this supercharger run a few times with distilled water, drain, and then fill it with the G05. Then, since I have a lab grade specific gravity tester, I will be able to adjust the antifreeze/distilled water mixture to my desired 50/50 ratio. Does this seem right, or is there an easier procedure/solution? (i read of dropping the IC radiator to get the fluid out)

Lastly, given that I found absolutely zero debris in my filter both times, and that the fluid that I removed both times looked just about new, I do not plan on using any radiator "flushing" product.

Any and all comments and suggestions will be appreciated.

Thanks and best regards -- Bob