What are some facts on Dexcool anti-freeze?

Factual Questions
1

Just about every automotive forum I visit, someone is bashing Dexcool. One of the most common complaints is that it gels up. I’m going to say operator error on this and that it is the operators fault if they start mixing brands, or mixing with the green stuff. I don’t know for a fact that it gels up when mixed with the older stuff, never tried it. So a few questions:

  1. Does Dexcool gel or solidify when mixed with other types of anti-freeze? I guess that’s possible, with chemical reactions and all.
  2. Does Dexcool gel or solidify on it’s own without mixing? If so, what causes that?
  3. Some claim that it eats radiators and aluminum in general, really? I would think new cars wouldn’t be around too long if that’s the case.
  4. How widespread are these problems with Dexcool?
  5. Dexcool is less toxic, true?

What prompted me to post this was a member on another site urging everyone to sign up at BigClassAction.com - http://www.bigclassaction.com/class_action/dexcool2.html
I don’t know the validity of this site.

2

I know the link doesn’t really state any issues with gelling. I just posted it to show that people have issues with Dexcool.

I bet most of these claims goes something like this, “My car broke at 140,000 miles because of Dexcool.” Maybe you had a leak?

3

1. Does Dexcool gel or solidify when mixed with other types of anti-freeze? I guess that’s possible, with
chemical reactions and all.
No. The disadvantage of mixing it with other antifreezes is reduction of its longevity. This is not because of some reaction occurring, but because of diluting it with something not designed to last as long.

2. Does Dexcool gel or solidify on it’s own without mixing? If so, what causes that?
It gels under long-term exposure to air, in other words, from air in the cooling system.

3. Some claim that it eats radiators and aluminum in general, really? I would think new cars wouldn’t be
around too long if that’s the case.
I don’t know about this, but I agree with your logic.

4. How widespread are these problems with Dexcool?
Again, I don’t know how widespread, but I would say that problems are common. Another problem is a greater tendency toward seepage out of cooling system joints.

5. Dexcool is less toxic, true?
No. It has an ethylene glycol base. Propylene glycol antifreeze is less toxic.

4

More info:

http://www.imcool.com/articles/antifreeze-coolant/dexcool-macs2001.htm

http://www.dieselsite.com/prodrev/coolmaint.htm

5

Thanks, some good info.

6

DexCool is still your good old ethylene glycol, just like the green stuff. The difference is the additive package. The DexCool additive package was formulated with two main goals: Eliminate silicone which is what destroys water pump seals, and to make it more aluminum friendly.

The weakness of DexCool is that it reacts badly with air. The vehicles that have had problems with DexCool (mostly GM trucks) had an angled filler neck and a radiator cap that tended to not hold pressure. This let air in.

I had a 1996 Camaro Z28 with DexCool. Changed it after 5 years and 60k miles. It still looked like new. Never had any trouble with the cooling system. I’m running my 1971 Corvette on DexCool for 3 years and no problems.