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Dex-cool good - bad - ugly?

Discussion in 'The Garage' started by k2-k5, Nov 30, 2006.

  1. k2-k5

    k2-k5 1/2 ton status

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    What is the lowdown on dex-cool antifreeze? Is it harmful to the cooling system. Does it breakdown, gel-up or otherwise ruin your cooling system.

    Appreciate your comments.
     
  2. gmc4cw

    gmc4cw 1/2 ton status GMOTM Winner

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    dex-cool was designed because antifreeze is bad. dex-cool is biodegradeable. the main ingredient is ginger root. you can drink it. if you drink anti freeze you will get really sick if not die. anti freeze corrodes aluminun. dex-cool does not. GM wouldn't change over to something unless it was better or cheaper. in this case it is better.
     
  3. Goose

    Goose 1/2 ton status

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    However, don't mix it with the other stuff because that is when it starts gelling.
     
  4. gmc4cw

    gmc4cw 1/2 ton status GMOTM Winner

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    X2, forgot to mention that. mixes with water though.:D
     
  5. GEORGIA GABE

    GEORGIA GABE 1/2 ton status

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    we had alot of problems from the first version of Dex-Cool, It was touted as being a 100k mile antifreeze.. then Gm found out that it does not coat metal and therefore does not protect it from corrosion unless in direct contact with it. There was a rash of gm vehicles esp. trucks with 350s that started having corosion and leak problems at the intake manifold... reason being Dexcool wouldnt protect that little bit of metal at the top where you get a small air pocket as the truck sits... We use the Zerex version now and have not had any problems.
    gabe
     
  6. b454rat

    b454rat 1/2 ton status Premium Member

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    The sh!t is junk. It deteriates gaskets and seals. Might be biodegradable and fine for animals, but sucks as coolant.
     
  7. k2-k5

    k2-k5 1/2 ton status

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    What about for older vehicles? And vehicles that would only see 1000 or so miles per year?

    Is there proof if deteriates gaskets and seals if so I can't see how they would keep selling it.
     
  8. 1979jimmy350

    1979jimmy350 1/2 ton status

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    the big reason that GM changed to Dexcool is becasue it help reduce cavation problems in Diesel engines, I had to change a heater core on a s-10 becasue the dumb asses who changed the tranny cut a heater hose and topped the system off with regular antifreeze talk about a mess to clean up there was a lot of crap in that system
     
  9. 4xcrazy

    4xcrazy 3/4 ton status

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    not sure if it's the same stuff, but i am running a multi-colored coolant in the Burb, usually run the green stuff, but was real low one day, and used a gallon of the red stuff from work, also some orange stuff another day,,,nothing really "gelling" in the syatem, there is however a very, very light film on the top of the water, almost like a super thin layer of wax or something.

    Still cools very well, no other problems except the obvious leak i have, to have to keep refilling the system:doah:
     
  10. ryoken

    ryoken Puppy Fabricator Premium Member GMOTM Winner

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    Dex-cool is a propylene glycol antifreeze.. As opposed to green, which is a ethelyne glycol...

    As far as I know, it's not a good thing to mix the 2, but have personally never seen the results..

    Musta checked 75 motors worth of antifreeze over the last couple months with my refractometer.. Gotta love winterizing season...

    We see lots and lots of the propylene glycol... There are 3 color variants that we see, orange dex cool, Cummins uses a blue variation and I've seen red..

    I have no real opinion formed yet on which I prefer, green or the new stuff... One thing I do know is the extended life, Dex cool is expensive...
     
  11. krechj

    krechj Registered Member

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    i use to performe lots of coolant flushes and i've seen some pretty serious gelling occur on vehicles running dexcool, i've heard it only happens when the two coolants get mixed tho. on newer vehicles that have been runnin dexcool since day 1 of their life i've never seen any adverse affects of it. as long as you're sure to flush your system VERY well i dont think itd be a problem
     
  12. TruckNutzDude

    TruckNutzDude 1/2 ton status

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    I've changed a few intake manifold gaskets on newer GM 4.3's, 3.1's and 3.4's and I can tell you there is some serious gelling happening inside an engine with dex. Most of the pockets in the heads, some of the heater hoses and water neck's were clogged solid. If I was a surgeon it would have been like flushing out the arteries of Ronald McDonald if all he ate was double quarter pounders and large fries. :rolleyes: I use the "all makes and models" universal anti-freeze in everything now.
     
  13. beater_k20

    beater_k20 Banned

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    when i was working at the dealership, i saw more than my fair share of gelled up engines because of dexcool. intake manifold gaskets HATE the stuff.
     
  14. peterpan

    peterpan Registered Member

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    i bought a 454 from a guy he ran dex cool in it for about a year he said after i put it in my tow truck and started it up i had to change every seal and gasket it touched thermostat intake head gaskets i won't run it in anything
     
  15. Can Can

    Can Can Pusher Man Staff Member Super Moderator

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    If it's that bad a product, wouldn't every single GM vehicle be in for a total gasket overhaul while still on warranty? They offer a 5 year, 100K mile warranty nowadays, and if Dexcool is as bad as you say there would be a MASSIVE amount of failures.

    How come the only place I read about this stuff is on automotive forums? How come I've never met a person in real life who's had a Dexcool-related failure?
     
  16. txfiremank5

    txfiremank5 1/2 ton status

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    I believe that most of the intake gasket failures were a result of a crummy batch of gaskets, that were poorly designed. I, and several friends who have/had late 90's GM trucks all had the intake gasket failure. Mine went in winter, and I elected to have it done, because it was unusually arse biting cold outside. The shop that did it, said they do them all the time... and routinely keep the "better" gaskets on hand. That was 6 years ago or more, and no issues. But, I also swapped over to the green, after a thorugh flushing, just to be better safe than sorry. I never add tap water to my rad, strictly distilled water to keep the impurities out. Zero issues to date since then. Before that I had all sorts of water related failures, water pump.. heater hose connections etc etc etc. (all with the factory dex-cool and no tap water added) In those days, I'm not sure what my mileage was, but probably only around 45-50,000 miles. Even now my 97 K1500 only has 85,000 so I thought it was strange that so many failures in the cooling system were happening.

    But, in my wifes 01 tahoe, that we had until July of this year, the Dex-cool never caused any problems... or I should say, the tahoe never had any water/cooling related failures.

    Maybe the dex-cool is better now, maybe the gaskets are.. maybe there was never an issue with the dex-cool at all. I don't know for sure.. but I just chose to stick with the ol' tried and true green stuff. I'm not worried about something, or somoone drinking it becuase when I change it out I get rid of it correctly. And I keep the system leak free, or fix it right away, and only use distilled water, so corrosion hasn't reared it's ugly head yet.

    All in all, I still think that the gaskets used back then were problematic, either by themselves.. or in combo with the dex-cool. The only gelling that I've heard of was when the green was mixed with the DC. So, if anyone switches over, make sure you flush the system very well.
     
  17. krechj

    krechj Registered Member

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    i'm fairly sure there were at least 2 versions of dexcool, i think gm recognized theyre mistake on the first version and has changed it to eliminate the gelling... dunno for sure tho just what i remember lol
     
  18. GEORGIA GABE

    GEORGIA GABE 1/2 ton status

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    yep, they changed the formula... also can man one of the reasons you didnt see as many failures in the cars verses the trucks is alot of the gm cars of that vintage have plastic intake manifolds...
    gabe
     
  19. 73k5blazer

    73k5blazer Unplug the matrix cable from the back of your head Premium Member

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    I've run it in all my vehicles since around 1999.
    1970 Impala 400, 1997 K2500 diesel (came with it), my K5 before I tore it down (due to rust), wifes old dodge spirit, '04 GTO (came with it), and 86 C10.
    I've had no problems in the old vehicles or the new.
    I've heard of these gaskets problems, but I don't know of any 1st hand stories.
    I think the one guy was right, they had some initial problems early on, and with the fact that they touted as 100k coolant, that it is not, but me, or anybody I know who uses it in old or new vehicles have had zero problems with it.
     
  20. peterpan

    peterpan Registered Member

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    the motor i had problems with was a 79 454 that had felpro intake gaskets with no signs of being installed bad they were soaked threw with the dex cool around the water ports
     

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