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The last couple of days I have read a lot about GM Dexcool problems and solutions; still not sure that I understand. I did experience it first hand with my 1998 Oldsmobile Intrigue. First seals replaced GM played the majority of the repair and the second time around not very much. However I am grateful since I read of many GM customers did not receive any financial assistance. I traded the Intrigue for a 2003 Toyota Camry and was not involved in the class action lawsuit.

Fast forward to 2012 and $4,500 rebates brought me back to GM and a Chevrolet Malibu. Should I have any concerns about Dexcool and engine seals or do anything other than follow the Owner’s Manual and keep the coolant at the proper level?

The problem with Dexcool is if the coolant level drops.

Dexcool is the early form of Organic Acid Techology. But it wasn’t realized if the coolant level dropped this OAT coolant would eat head gaskets, heater cores, and radiators.

That’s why I tell owners of GM vehicles with the Dexcool, “As soon as the vehicle is out of warranty, bring it over and I’ll flush the cooling system and put in the universal coolant”. And the problem goes away.


So the gaskets are still made from the same material and Dexcool still has the ingredient that dissolves them if air gets into the system; no gasket material change or Dexcool reformulation?

What level do I keep the coolant at? I saw some comments that it should be at the warm temperature mark in the reservoir even when cold?

Can I have the coolant acidity level tested regularly to determine if air has got into the system or is there another test to determine if air has gotten into the system?

Just follow exactly what it says to do in the owner’s manual. That includes keeping it at the “full cold” & “full hot” marks (or whatever they’re labeled).

Then, as Tester said, once the warranty period is up, I’d ask someone to get the car changed over to something else such as the newer “universal” coolants.

If you’re in it for the long run with this car I’d also suggest NOT following manufacturer’s recommendations in at least one respect - have the cooling system serviced more often than is specified. GM is probably still saying DexCool is good for 5 years / 150K miles. I’d maybe go as far as 3yrs/36K miles. But, even though newer coolants do profess to be “long life,” I still like the old fashioned 2 yrs/24K miles for a drain & refill of the cooling system.

Doing maintenance sooner/more often than required doesn’t present a warranty issue. Its also the case that any qualified shop can do the work. If you’re worried, find a local shop that actually specializes in car HVAC - such as a “radiator shop.” They will probably know more about GM cooling systems, DexCool, servicing, etc. than the techs at the dealership.

I usually give the same advice as Tester. As soon as the factory warranty expires on a GM product, I recommend flushing all the Dexcool out and replacing it with normal universal coolant, and I recommend it be drained and refilled every 2-3 years.

I agree with the others. I had a 2006 Chevrolet Uplander which had the factory Dexcool. I had no problems, but before I sold the Uplander to my son, I had the Dexcool flushed out and replaced with universal coolant. This was at 75,000 miles. The Uplander now has well over 100,000 and had no cooling system problems.