Thread: Heater Core

Originally Posted by GTPluv

I have that orange Dex cool crap. Mine is all gunky too.

I feel for ya.

Well I was always told it was exposure to air. But, there is air in every cooling system. Cavitation in the pump, air in the radiator (its very unlikely every void has been filled in the radiator) and so on. So I dont know what to make of that claim. Seems plausible and if it is the cause then you definitely dont want to use it. I drive a lot of highway miles and still got it so it can be engine temps or short trip driving.

Dex-Cool is LITERALLY the only coolant I have ever seen do that. None of the green, yellow or red coolants I have seen used have ever done this.

The company who made a large batch of DexCool for GM actually admitted that they made a bad batch of it. GM says no, but it is documented somewhere what happened, in the companies point of view what happened, as its a huge problem with many GM vehicles. But the problem has been corrected, but that didn't stop many from flushing and going back to the green. 500,000 miles my foot.

Many thought it would do this with exposure to air, not true.

Many thought it would do this if your using tap water, not true.

Many thought you have to only use distilled water to avoid this, again, not true.

37K miles, mixed perfect 50/50 using filtered tap water, not the reverse osmosis system we also have and it does this? Her car was a rebuilder we did case we got it cheap, and 80-85% of her front end is all brand new, including many new engine parts for the sake of replacing them to avoid problems.

The GFs 1997 GTP had DexCool in it, and has had the system flushed at 100K miles, and DexCool put back in. Her coolant didn't look bad then, and still doesn't today.

I have seen some cars where the thermostat housing was almost completely corroded through due to the coolant.

But to flush out dexcool all the way, I used a lot of water, and some stuff thats added into the system, and thats the real cleaner there. I posted it before on the "other forum" what I used, and it worked great. I can find out what it was for ya.

~F~

Absolutely, would love to know what it was.

Yeah, the thermostat is good. I had hoped it was something simple like that.