Hey guys, you were a huge help when it came to rebuilding my 97 SSE, but sadly on christmas eve i was rear ended and they totaled my car.... stupid insurance companies. but anyways yesterday i bought a 99 Lesabre Limited, very nice ride all the bells and whistles, just as nice as my Bonneville. But i have a few questions, what color is dex-cool coolant usually? I am aware of the fact that this stuff turns acidic after a while and im worried that it may begin to eat away at my gaskets. I am also aware that if you mix glycol coolant with this dex-cool it will gunk up, the resivior on the fender wall has pink coolant, and the radiator has green coolant, and im worried that it is glycol and that it may begin to gunk up. Finally if the case is that you guys suggest my to flush the cooling system, should i replace my lower intake gaskets and upper intake gaskets? Just to save my own hide from any further problems? The advice would be greatly helpful. Thanks guys

Dex-cool is orange, 5yr Coolant from GM for GM
part# 12346290 - $25.07 +tax at the dealership

beware, do not mix green and dex-cool it will not be pretty for your radiator, water pump, or motor in general and it turns black lol
black fluid is never good hehe

I would flush the system completely and go with dexcool but it is expensive, cheaper at autopart stores but still pricy... and it prolly wouldnt hurt to replace the gaskets and the thermostat IF they mixed... but like i said, if orange and green mix it turns to black and then gets sludgy, if its still green i wouldnt worry too much. Btw if its pink, not orange, its... mopar coolant (dodge/chrysler)... but what oddball would do that i dunno, but i wouldnt let it mix either just to be safe

personally, I don't fall for the DEX wrecks gaskets. Neglect wrecks them. However, if your going to change your coolant, as you should. Get the green. It'* cheaper. Just flush the system real good and then fill it back up. You will need to bleed the system real good to get all the air out.

I saw a comment from someone that MoPar has a certain type of long life antifreeze that is compatible with the DexCool. If that is the pink, there may not be much to worry about.

Am I wrong that there are two green coolants. The older style with silicates in it is green. This is not long life and does not mix with DexCool. Then there'* the slightly green Mixes with All Coolants and Colors by Prestone that I got at Walmart for $9 gallon with a $5 rebate up to 2 sticker on the front of the bottle. (Save the foil seal for rebate.) That is a long life coolant that mixes with anything.

I drained my DexCool. I put in water and warmed up to circulating temp. Cooled then drained again. Then repeated. Little DexCool color left but slight orange tinge.

I refilled with Mixes with any color. Warmed to temp. Burped the heater core by running at 2500 rpm for 10 seconds a few times. Bled at thermostat housing. And went merrily on my way.


The old style green is not recommended because it doesn't protect the various metals and is abrasive. If you're not sure what'* there, I drain and replace with DexCool or Mixes with any color. You'll know you have fresh, long life antifreeze. In two years drain and refill. BTW the new DexCool formula appears to be the same as the Mixes with Any Color formula. When the deterioration of gasket seals was discovered, it seemed to me from what I've read that DexCool antioxidation chemical was changed for a different one. So the newer DexCool and Mixes most likely are the same formula with color differences. That'* my opinion.