cturboaddict

I also didn't know that you could switch to standard green. I always heard that Dexcool lasts much longer than good ole neon green kitty cat poison drink.

Grizzly old man

That's the main reason I had it done instead of doing it myself. I probably could have driven it home and used my Prestone flush kit but I wanted to be totally sure all the clumped Dexcool was out.

I'm pretty sure since they were an actual Chevy dealer that they did a better job than I would have at home.

donbrew

240F !!!! that is when the ECM tells the ignition to fire every other spark cycle. That is the bucking that you initially noticed. The fan comes on at 220F, 20 degrees F difference. Very soon after that the engine will shutdown in an attempt at self-preservation.

If you look real good in the reservoir, assuming the pressure cap is doing thing right you'll see it. Or look under the pressure cap.

The reason people don't like DexCool is because they don't understand it. It is in there because it tends to seal small imperfections that appear when the engine gets hot. The green stuff works in a different way, however they say the yellow stuff will work in an EcoTec engine. Even the "green" bottle says something about uses in Aluminum. I know that nobodies mind can be changed, but the Saab engineers had their reasons.

Does anyone remember the great anti freeze class action suits of yore? The Green stuff ones, anyway put a huge company out of business (can you remember the name?). The stuff did not know when to stop sealing and the radiator cores got blocked. The Orange stuff suits turned out to be the engines were not built right.

Anyway the green is a different type of chemical than the orange. They do their jobs in different ways. My suggestion is if you really have a problem with DexCool use the Yellow Long Life (usually a red cap) stuff instead, avoid the green. But then I'm of Irish Protestant heritage.

cturboaddict

Okay~

She returned today, and said she noticed no puddles or smelt anything odd at work today. She said the car never got over 175 degrees and I checked her reservoir when she got home. It was at halfway when warm. I'm keeping an eye on it daily to see if it drops at all.

Weird...

donbrew

One of the key observations is if the reservoir level increased when engine at operating temp, then goes back down to the same "cold" level. This is checking the pressure cap, they do go bad and do cause badly diagnosed problems. Also check the upper radiator hose after cool down, if it collapses there is a whole different set of problems.

blacky

Today, anti-freeze type cannot be identified by color.

When all of this started there was EG with conventional additives that plated surfaces and reduced cavitation erosion in the water pump. This was usually green. Plating reduced heat transfer, but protected surfaces left uncovered by low coolant level.

There was extended life antifreeze too, which was EG with carboxylate-based rust inhibitors. My understanding is that water pumps had to be re-designed. Since these don't plate surfaces, there is no protection for surfaces left uncovered by low coolant level.

EG is poisonous, but is 100% biodegradable to carbon dioxide and water.

There are hybrid chemistry EG coolants as well.

Colors are all over the place.

DEX-COOL is EG with carboxylate-based rust inhibitors and an orange dye.

Since DEX-COOL and what we refer to as "conventional green" are both EG, they are about equally poisonous.

l have only good to say about DEX-COOL. The silicate deposits with conventional additives are totally absent. I've seen aluminum, brass, cast iron, and steel from heavy duty engines come out essentially free of pitting and corrosion after 400,000 miles. Radiator tubes clean as a whistle.

blacky

Computation was for any 8 qt system. Like I said - round numbers.

No 2.4 l stuff./

Earlier I mentioned my own experience with consumption of coolant. There was a response to the effect that that was a problem. I showed that it was not. The 2.4 l engine only came in because that's what I drive. Making up a pint in 15,000 mi over a year is very little, regardless of 2.2 l or 2.4 l. I am sure that much water could evaporate from the overflow reservoir, which is located in a hot place.

cturboaddict

It seemed this morning after sitting all night that the reservoir was lower than when I checked it yesterday. I'm waiting until she gets home from work to check it again.

donbrew

The amount of change is not that important, just that it does change from cold to hot, hot to cold and that the cold level stay close day to day. You are being lucky, so far.

One thing I found on my 2008 was that the weep hole on the water pump is in a pocket on the top side of the pump. Pure genius there. But what happens is when the pump starts weeping the DexCool starts trying to plug the leak but it's in a pocket so the pocket fills with the "clumped" DexCool which is also evaporating and you never notice that you have a bad pump, or low coolant if you don't monitor it. Was that a run on sentence, or what?

cturboaddict

No.... I got ya. Monitor it. :)