Dex cool in a older GM

[weasel]

my car is a 1995,a year before dex cool had come out. ive been running green antifreeze in my car up until my lower intake gaskets went out in 2011.after they have been replaced i switched to dex cool and have had no problems since. ive done some research and found that a GM with a aluminum engine cooling system will be better with dex cool since it doesnt corrode so much.has any one else done this and hasnt had problems? and whats this big thing about that it eats your head gaskets? from what i heard it was GM's new radiator caps they came out with in '97 that caused that problem or am i wrong?

[3400-95-Modified]

I don't run it, Just never liked it after the issues it had... I run Peak Global Lifetime coolant in all of my cars. Can't complain since that's designed to run in a Subaru which is a 100% aluminum engine.

[Superdave]

I've chipped away the sludge it leaves in a block, nasty stuff. Only the green stuff in my Camaro.

My DD ('03 Avalanche) and the wifes DD ('13 Malibu) both run it fine though. I've got 150K miles on the truck and have no problems.

[weasel]

hmm,one thing i dont get,is if it is such a problem why does GM keep using it?

[Z26-T]

hmm,one thing i dont get,is if it is such a problem why does GM keep using it?

GM and (I believe) all manufacturers are using "OAT" coolants. GM was just one of the first to start utilizing it. OAT means organic acid technology. OAT coolants utilize an organic acid to prevent corrosion in the cooling system. Green coolant uses IAT (Inorganic additive technology) which uses silicates as its primary corrosion inhibitor. Silicates are abrasive in nature and can cause damage to water pump seals and cooling system components if they drop out of solution. Which is why green coolant has a much shorter service life than dex-cool and other OAT coolants.

There is a lot of controversy about dexcool eating LIM gaskets on our engines. I've seen LIM leak on systems using green and dexcool. Dexcool does often turn into mud if you don't service it before you hit the 150k-5 yr recommendation. I just recommend servicing it around 50k. I use it in all my cars with no issues and love it.

[geoffinbc]

Agreed most problems are due to lack of maintenance or even simple visual checks that could be done by the owner. My family drives all GM vehicles and none have had sludge buildup. My brother had a 97 Sonoma which one typically one of the bad ones. But by making sure the coolant was full, the cap was in good shape and it actually got its coolant changed he never had an issue.

The gasket eating issue may be true. But remember all the car manufacturers buy parts from different suppliers so one day there is bound to be a compatibility issue. All cars on the market use OAT coolants so I think the problems are all solved.

[weasel]

agreed,my dads 1997 checy truck has the original dex cool in it and the motor has never had gaskets done to it yet.i guess people do the usual blame the dex cool even though i dont know what mainitaing my car does