ck76239

Hi guys, I have a question, not about my z28, but about my daily driver, it's a 2000 Chevy S-10 4x4, with a 4.3l V-6.
Last winter, I noticed the heater didn't seem to putting out much heat, so I had the cooling system flushed.
Now, I turn to heat mode for the first time in the season, and no heat at all. I have a trusted mechanic (he was one my scoutmasters when I was growing up)I go to for work on our family car etc. He told me the Dex Cool stuff gets sand size kernals of crud in it, if not properly maintained. I asked if if he could switch it, and go back to ethylene glycol, but he said he wouldn't reccomend it...
So what's the deal with Dex Cool, what makes it go bad, if indeed it does?

86IROCZ

Hey, I have the exact same s-10 and the same thing happened to me too!

I had to flush it a couple of times to get all the sludge out. Its been working fine for the past year, but I yet to turn on my heater

IROC212

iTrader: (1)

I never had that problem in my thirdgen, but experienced it with my old Jeep. I flushed the system completely and put dex cool in it. About a year later the Jeep's radiator was full of red mud. I don't know why, but so much for 5 year coolant. I put green back in after a radiator replacement no problems now.

ck76239

Well, he backflushed the whole system, and now it heats great. I just hope it keep gunking up, because I dont want to pay to have the heater core replaced....

Are there any other alternatives to Dex Cool???

Ck76239

PhLaXuS

Is the GM requisite for DexCool that it's a new (like 97+) engine with an aluminum block?

BMmonteSS

We had the same problem in our 99 blazer, red mud in the heater core. Like mentioned above just back flush the heater core and that should take care of it.

tad1214

Just thought I'd chime in here. I work a t a Tires Plus this time of year we always check the coolant for temp resistance and cleanliness (spelling?) Anyways, dexcool always gets a gummy mucky residue to it. Just a radiator flush 90% of the time cleans it all out. Want to check if it needs it? Pull off the radiator cap (WHEN ITS COOL PLEASE!!!! Dont want a fellow thirdgener scalding there hand, ive seen it happen, its nasty.) and look at the rubber gasket, if it has a brownish residue on it, then its time for a flush. I dont know for sure but ive heard the multi use coolant that works in all types of systems doesnt do it as bad. Just another event that GM engineering is at work! Also, please dont mix the green in with the red, it has to be flushed then... if its low add water for the mean time. Remember to rotate your tires every 6000 or less miles! :-)

MY87LT

iTrader: (2)

Stay away from DEX COOL. Horrible nasty stuff.

dave4x4

I've been using Dex-cool in my 2001 Silverado and have never had a problem since day 1.

I hear that you're not supposed to mix the green and orange coolants, so if you go back to green, make sure to flush all the Dex-cool out, although this is probably easier said than done.

SIEB77

most trouble with dex cool is when air gets into the cooling system. Thats when the crud will start building. Like on s10 pickups with the 4.3 when people ignore the leaking intake gasket it will usually crud up very soon after. Otherwise a very good coolant that will outlast green for a long time.

safemode

iTrader: (1)

dex-cool is crap. It was crap when they brought it out in their new vehicles and it's crap to even think about putting it in a vehicle that didn't come with it. It coats _everything_ in an orange film. It gets crud buildup like mentioned by others. It was meant to reduce maintenance between coolant flushes. I have pictures posted on here somewhere of my thermostat and radiator cap and such... i'll have to just look at the webserver sometime and re-post them.

Basically, dexcool reacts with air when hot and it undergoes a chemical change and the molecules start stringing together and becoming very large. This becomes the "cludge" that you see buildup. So any sort of coolant leak, benign or not, becomes the end of your use of dexcool.

It doesn't cool any better, it was meant only to prolong maintenance.

redbird92'

iTrader: (1)

Yeah i have a 1998 jimmy 4.3L and I have had that same problem after many attempts to clean with the name brand cleaners without much success with it.

I made my own cleaner and it is fantastic, cleaned the gunk beyond expectations maybe I will patent it someday

DEXA-COOL === costly repairs

Aaron91RS

iTrader: (2)

I took our 95z26 apart.
dexkill had coated the entire engine even below the water line.
blew out a head gasket and also previously had eaten up the usual lower intake manifold gasket..

The stuff is beyond garbage. I don't care if you keep all the air out. The stuff is crap and will cling to everything inside the engine even below the water line.
Where my heads meat the block, all the passages were 3/4 closed over from red crust.

GM got sued and lost for a reason. The stuff is garbage!

MY87LT

iTrader: (2)

Oh I flushed the Dex Cool out of my car and made sure that I absolutely got all of it out. Took me pretty much all day, but I did it. I just did this a month ago and will flush the system again in a year just to be on the safe side. Seems like a waste of green (both fluid and money) but I dont want to take any chances.

safemode

iTrader: (1)

You'll be happier not having every damn thing in the car that touches coolant stained orange and encrusted with crap. That's a bigger waste of green.

Wadebryant

Class action suit has been brought against GM reguarding DEX Cool. It may be too late now but, you may be entitled to reimbursement for repairs. It's up to you to do the research.

Start with a web search on the class action topic.

igotta355z28

iTrader: (1)

DEXCOOL is a HOAT coolant or Hybrid Organic Acid Technology, The problem lies with the fluctuation of the pH of the coolant. The pH is supose to be a lil above about 11. If the ph rises then it becomes caustic and produces a scaling that covers everything and can lower the cooling efficientcy. And well if thats not bad enough if the pH gets lowered then the hole mix becomes accidic and will eat your engine from the inside.....

1985blktransam

iTrader: (1)

Did not care for Dex cool myself. Recently upgraded my cooling system, New GM Radiator, Thermostat, Hoses ect.

Difference here, I went with Evan NPG + Waterless Coolant. Car runs cooler and does not need to be changed.

Con is that the system needs to be rid of any water. The other is the $30 per gallon price tag. For me ,well worth it. I converted my daily driver as well with Evan coolant. Since I was redoing it anyway, had the block drained and worked out well.

http://www.evanscooling.com/

And I do not work for Evans, I am in IT !!!!

safemode

iTrader: (1)

Running cooler probably has more todo with the new components than with NPG+. NPG+ will actually run hotter than the same system running on 50/50 regular coolant (assuming the engine is operating at normal temperatures). The deciding factor here is boiling temp and specific heat. As long as you can assume your engine will not have many local temperatures above the boiling point of your coolant, and that the avg temp is well below this temp, then the coolant with the higher specific heat will be best. Within the operating range of water, water is the best. If things get a little hotter than what water handles (like in car engines) then a mix with antifreeze is the best. If you get even hotter (or want to run hotter, as hotter engines are usually more efficient if they can handle the heat) then you use NPG+.

The reasons to use NPG+ have more to do with what you can do at the higher temperatures that would be dangerous with normal anti-freeze and water mixtures. In addition to the decrease in maintenance. It would not, however, give you a cooler running car for a normal application, it's just not nearly as good at absorbing heat as water and 50/50 type mixes.

http://www.evanscooling.com/main25.htm Pretty much sums it up.

MY87LT

iTrader: (2)

It's all right for a company to develop a new product. But they need to bench test it more and really find out what the final effects will be instead of putting us through hell.