Just wondering everybodies thoughts and experiences about dex cool. I havn't had problems but recently heard from a couple friends that its horrible.

 

Well i just put a radiator & motor in my car the dexcool was black & clay looking

 

Dex-Cool in it's early days got a bad rap because it's original formula promoted nylon gaskets to go bad. Now when I say EARLY formula, we're talking mid-late 90's. Today's Dex-Cool is no more harmful to nylon gaskets then the good ol' green stuff.

The problem with nylon intake gaskets is the nylon, it's a crap material and gets brittle from hot coolant and engine exposure. My 3100 powered '94 Grand Am has had two set of nylon gaskets that went bad (originals and the Fel-Pro ones I installed). In my owner ship at 86K miles back in '03 to today at over 210K, I've ran NOTHING but the green stuff.

I continue to use the current Long Life Prestone with Dex Coolant. No issues worth noting. Just do regular maintenance as recommended and you should be fine.

 

Also have heard stories about Dex-Cool but never had an issue with it. I had the coolant flushed in my 03 Monte at 38k miles and rolled the mileage up to 150k, without another flush, and never had an issue. Just recently cleaned out the overflow jug in my 06 because there was a bunch of nasty buildup on the inside surface.

 

When I bought my Dale Jr., the coolant had been replaced with a green type but there was still traces of Dexcool in the overflow bottle as well as in the radiator. I flushed the radiator out multiple times until the water came out clear and even used Prestone flush on the first time and I still had a coating of brown gunk on the inside of the radiator that would not come out. This was with running the car on each radiator flush so I could get everything hot.

I personally don't like Dexcool. I ran it in my 98 Chevy truck which I bought new until last year when I changed it to Prestone long life green coolant. I also had my intake gaskets changed three times since new so I don't know if Dexcool helped to cause this problem or not. Currently I have one of the revised intake gaskets in it but not the latest revision so who knows if it will hold up or not.

I do have the latest version of intake gaskets on the Dale Jr.

Wayne

 

I got the Dexcool out of both Months. I only run Preston now.

 

I got the Dexcool out of both Montys. I only run Preston now.

 

i run prestone too, my dexcool was original, 75k miles and it was kinda ugly but not horrible

 

FYI - I don't know the exact timeline when the Dex-Cool formula was modified, but I think '98 was close to that time. Anything 2000 and newer should have the modified Dex Cool that doesn't have a problem. Granted, switching to green doesn't harm anything, but if your only reason to switch to green is fear of Dex, today's Dex is not any more harmful.

Also, if the intake gaskets are nylon, they are still junk. It's aluminum if you want to avoid issues.

And to those noting sludge in the overflow bottle, I've seen it with the green stuff, it's not a Dex exclusive. Like anything else, don't clean it or flush it regularly, it's going to gunk up.

 

I cleaned mine out for what looked like the first time. Car has 76k miles on it and the jug looked pretty bad. My coolant level was low in the overflow anyway so I decided to clean it out before I refilled it.

I know GM runs their orange-colored Dex-Cool 1#12346290 in the 06-07's, that's what I'm running in mine right now. I can't say for sure if that's what they run in the 00-05's. I think it is, and I'd assume so, but I can't remember or say for sure. Like The_Maniac said, the newer Dex isn't an issue.