the original dexcool went 35k on my monte, and moms 2003 impala went less. both cars were only a few years old. i was pretty upset to find a permanent brown stained reservoir. now all cars i have and work on get the all makes prestone extended life as soon as i can. my monte has 165k and a few more flushes and i still have the brown reservoir. no gasket failures though on either the monte or moms impala.

What color was the sludge? Dark brown or light brown? DexCool is not invincible like many people may be led to believe. Air pockets in the system or even a slight mixture with a different kind of coolant will foul up the DexCool in short order and turn it into sludge or gel. It needs to be replaced at minimum every 5 years or 150k miles as well.

Gasket failures occur on 60*V6 engines regardless of coolant type used. These failures date back to the early 1990'*.

looked like coffee flavored yogurt, and both cars were virgin and less than 30 percent of the recommended interval. no air pockets that i know of because i do the main. and i didnt even remove the cap until then , i only looked at the bottle to make sure it was at the line.

so if so many of those engines did have failures why not mine or my moms. I think it was because i got rid of the dexcool so early.

Dexcool itself is not what kills the gaskets. Its the acidity in the coolant that kills the gaskets. The sludging up, as mentioned by one of the admins before, is due to either mixture with other coolant types, or air in the cooling system. This would clog up the radiator and overheat the engine, not blow your gaskets. I wouldn't put it above GM to fill the car'* cooling system improperly from the factory, lol. It is likely that there were air pockets in the system without you knowing about it, as air in the system will result in light brown colored sludge and this has been proven.

That being said, I would keep an eye on it. Don't get me wrong I'm very, very glad that your coolant has held up so well thus far because LIM gaskets aren't fun, but just keep in mind its the acidity, not the sludging that kills the gaskets, and all coolants will get acidic after some time and will need to be replaced.

The original Dex of the Lawsuit had a life expectancy of 100k. A variety of reasons including the gasket etching proved out that it did not last that period. It has since been reformulated and those gaskets not used since 2003-4? The New Dex formulated after the lawsuit is warrantied for 150k and tests seem to prove this out. So alot of the debates here, is welcome to yesterday.....Whether a manufacturer other than GM/Havoline says it'* Dex compatible or not is only as credible as that maker. I wouldn't add any other formulation with Dex. Although if your going to switch, I would certainly advise using one that states so because of residue. I've been using Dex for 16 years and never seen it go "milky" without being adulterated. I did have an S10 where it went "staining brown" after a bad overheat. None of us are lab scientists, and what seems like credible evidence on both sides (Again, regarding old original Dex) floods the internet. So why waste the breath and effort. If you feel it'* not for you, don't use it. For others, that'* their business.

For myself, I've been using it since it'* inception, I have always changed it out like any antifreeeze @ 3 years/50k miles and other than the overheat incident (bad water pump) have had 0 problems. The GXP was changed out with the old slightly darker but still let light through. It was replaced with new Dex. Using other than manufacturers recommendations voids warranty for those like me that have one.

8 months and only 36 votes???
Picking up heads today, last of the Rock Auto order coming tomorrow.
After 3 flushes with plain tap water before teardown, I guess I'll do one more with distilled water after re-assembly, and then then use the Pres-Dex...

I'm gearing up to flush out my radio when the weather gets better, but it'll just be a hose out and dex (already have it sitting around). I don't have a job and limited funds, so 80 dollars or however much it would cost to take it to a shop (as well as not knowing if theyll actually use what I give them) to get a flush is too much for me to handle right now.

It'* interesting this thread has resurrected itself in the past couple of days. I had been planning to change my coolant tomorrow for a few days anyway and for the record I bought Prestone Dex 50/50 to do it. Northstars love dexcool and wouldn't put anything else it.

Ugh, radio? I'm having brainfarts galore tonight

I use fleetgaurd (cummins) its enviro. friendly they say its drinkable non toxic( not me after its been run ) and can be mixed with any other antifreeze.