Originally Posted By: 1 FMF
fwiw i just changed coolant on a 2001 mercury (ford) grand marquis with the 4.6L engine. it had a stuck open thermostat so i ended up doing a coolant change since it has 107k on it. It was green coolant, and I don't know the history of the car so it may have been messed with but there's been a lot of criticism on cooling systems having unpressurized or open to atmosphere coolant recovery bottles and that when coolant flows into it when hot the air in there (oxygen) deteriorates the coolant in the overflow tank and causes sludge and whatnot. Well on this coolant overflow tank on the grand marquis, which is pressurized and the entire cooling system is a closed system, the tank was a disgusting mess inside. The plastic which is translucent white, was all coated on the bottom with greenish brownish sediment and it took me longer to clean that than do anything else. And this was not dexcool coolant!
The '01 Ford cars original were filled with Green.Ford says only use Green or G-05 can be used. G-05 and Green and Dexcool for that matter are generally compatable but it's best to get a full refill of one or the other. Green needs to be changed every 2 years. If it's not changed it will turn brown and sludge that's true. When people say Dexcool doesn't tolerate air they are saying that it will wreak havoc in specific situation withingn a few 1000 miles if air was trapped and you have an iron engine especially. It's a little bit different of a phenomenon.
Quote:
Quote:
Why? GM says every 5yrs or 100k miles -- you know more than they do? Where did your engineering degree from?
my degree is from rit but just because you have a degree or have an sae certification doesn't mean you're a good mechanic, or good at anything for that matter.
GM has come out with some [censored] over the years and while i don't follow gm history that much i'll use as examples the ford/navistar 6.0L diesel and all it's problems it's had during it's run, and the one i love to use the most is the mercruiser (as in marine) 3.7L model 470 which was an aluminum block with cast iron cylinder head which was the biggest piece of [censored] ever made; so when people say do what the manufacturer says as in they are always right, anybody with clue should be going
In fact, didn't the government just bail out GM? Nobody has ever had to bail me out financially like that, so yes I guess I do know better than GM.
and to get back on topic, for the original question of should i use dexcool/deathcool, yes. You can read about dexcool at
www.imcool.com and search on my username for other links i've posted about the issue. Dexcool has had problems in certain applications which there is a logical reason for and has been fixed, and in the vast majority of other engines any coolant problems are caused by other things and it is not soley the fault of dexcool and would most likley happen with any antifreeze. So use dexcool, unless it costs you significantly more $$$ to obtain but it shouldn't, it's readily available at walmart and as cheap as the supertech or no-name brands which i will argue is better than those per the following:
this is what i've learned from various sources such as NARSA, imcool.com, motor magazine and others, and be warned this is limited information that i know of;
all antifreezes are ethylene glycol & water, where they differ is in the additive package which provides the corrosion protection, alkalinity, etc.
I believe although not entire sure, that most of the antifreezes today use sebacate as one of the additives, and this is compatible with all the other additives is my understanding. Here's how they differ,
*dexcool uses 2-eha in addition which differentiates it, dexcool is silicate and phosphate free and whether silicates & phosphates make it incompatible I'm not fully sure but i tend to believe they do because i gotta believe there is some merit to the warning behind mixing coolants,
* asian formula's use phosphates, instead of silicates and 2-eha;
* g-05 uses low amounts of silicates and no phosphates no 2-eha.
so from this perspective you can easily see how they are not compatible. But how can you buy prestone, zerex, supertech antifreeze that says compatible with all makes & models ? well they cheap out on the additives and use only the common denominator, maybe just sebecate, and they claim silicate and phosphate free (and to claim 2-eha free would be way too technical). And this example is by no means complete, it's just an example from what limited information i've come across from what i believe are reputable sources over the years.
All the antifreeze makers claim proprietary additives, which i think is b.s. for the most part, but is the main reason why no one understands what the [censored] is going on with antifreeze these days, it's a fear tactic along with withholding information to force you to by their product.
I agree with your sentiments. What we found out is that most of the all makes is dexcool and contains 2EHA. G-05 contains benzoate as an OAT and is fairly begign as far as being a plasticizer which 2-EHA is accused of being. Sebacate is mostly only used in Asian OE coolant. It's not really a known quanity for being a plastic eater or not, but it doesn't appear to sludge as much. Texaco Dexcool contained sebacate along with 2eha, but most other brands of Dexcool contain 2EHA but not sebacate and use another inhibitor.
I think Dexcool works fine in models that were validated for it, especially later models. I don't think it is a good idea to put in older models that weren't validated for Dexcool.
GL
