I read several threads on DexCool and am still not sure.

I have a '97 LT1 Camaro that *had* DexCool in it. I have always been impressed with how cool the car runs even in blistering heat, and I often wondered if it was due to the DexCool. I had a '95 that ran really hot sometimes.

1) Leaving the damage/crud issues of DexCool aside for a moment, does it actually *cool* any better? Why?

2) How complete of a flush is 'safe' to go back to Ol reliable Green Stuff if I decide to do so? I had my motor out and drained the block as completely as a person can without actually disassembling the motor, but for sure there will still be pockets of the DexCool in there somewhere and I don't know how much is too much to mix with the old green stuff because I don't really understand why mixing them is bad.

3) What the flagnard is wrong with my X-Wife??? I know this has nothing to do with DexCool (ok really no way to be sure but probably not) but it never hurts to ask the question. Never know where you'll find the most important answers.

Thanks.

 

Dexcool is not that radically different from green, don't think there is much if any cooling difference. What you saw was likely the result of system condition.

I never had any trouble with Dexcool.

These days I am running the "mix with anything" yellow.

 

1) I have not noticed any performance differences between Dexcool and the green stuff.

2) You can mix them all you want. Won't hurt a thing other than lowering the protection properties to that of the lesser coolant. A small amount is certainly not going to hurt anything.

3) How the heck should I know.

 

1) Dexcool seems to last a little longer that the other stuff.

2) From what I understand if you mix them the could gel.

3) That's why shes your ex-wife, don't try to understant it.

 

Urban myth, wive's tale, whatever. Simply not true. Never has been.

 

No no, he's completely right! She's my X-Wife and I shouldn't even *try* to understand her!!!

 

I had dexcool and after many problems I completely flushed it. It turned into a orange sludge from either someone mixing it or after air got into the system. It may have been an older form of the current dexcool. The car was very well maintained. I now only use the old green stuff concentrate with 2 gallons of distilled water. I've had no problems since.



I filled and flushed it many times to get the old stuff out. I also ran it with the hose going through it until I saw clear water. Draining by pulling the knock sensors is a good idea also. I'm guessing that's the same on an fbody.

 

I have seen systems that had a brown like substance in the radiator, when the green and dexcool was mixed...

Do not know how old mix was, or ever flushed...

 

Air and Dexcool was the issue. Not mixing with older coolant.

 

You can see the "brown like substance" in a completely Dexcool system. It generally mixing with air that causes coagulation-not mixing coolants.

 

When they went to the 100K target coolant life they also put clay stopleak in the systems right from the factory. This caused heat core blockage in many a garage queen causing people to complain about Dexcool. Again though Dexcool was not the issue the clay was.

 

Finishing up my 383 swap today or tomorrow and I'm going with some CarQuest green coolant.

 

I decided to go with the Ol' Faithful Green Stuff too. If there isn't any real cooling benefit to the DexCool then I don't see any reason to mess with it.

Plus I always have Green on hand for my Van, wich seeps out the freeze plugs.

Sometimes I like to mix it with a Screwdriver or Vodka/Lemonade too, for a little extra 'kick'. So it's good to have around for lots of reasons.

 

OK so I'm the OP (cue Andy Griffith theme song) of this thread from the dead, but I came back to it because I think the history of my coolant is relevant.

March 2009: I posted this thread, because I was putting the engine back in the car and 'converting' from pure Dexcool to pure green stuff at that time. I had the engine out of the vehicle, drained and rinsed the entire cooling system including both the radiator and block outside the vehicle, and put it back together and in the car with good ol green stuff.

Summer 2010: Cooked both head gaskets. (Presumably completely unrelated to any coolant or cooling issues.)

Spring 2011: New heads/gaskets and once again, flushed entire system while engine was out and disassembled, and again put it back together with good ol green.

Right Now 2011: Has run cool as a cucumber since the new heads/gaskets. Even in the summer heat the car never got over 210. (Has 160 thermostat and programming to match.) I am right now replacing the radiator due to cracks in the plastic tanks. I took the cap off to find this crap covering everything inside of the radiator.



The coolant itself looks perfect. So, I drained it into coolant jugs and it looks just like new, it's not brown like you'd think given the crap on the inside of the radiator. The brown residue is only on the surfaces, not mixed in with the coolant, and it's just a surface 'covering', not corroded into, or plugging, the radiator rows.

Point being, in about 2 years, this system has been completely flushed twice, and has had brand new coolant twice, and I'm not sure what the residue is or if I should be worried about it given the car runs nice and cool. Is there some kind of additive I can/should put in it when I refill it again today with new coolant? I have to assume all the hoses and inside the block have this same residue?

 

Back in the Vietnam era when agent orange was used and later found to be very, very bad. The government sat down and thought about how to get rid of the surplus .... We will just stick it in cooling systems of cars hahaha ....

Honestly that orange crap trashed my 97 camaro's cooling system bad!