Question about Dexcool coolant

Ron3rd wrote:
OP here; just to clarify, no leaks are present. Was just wondering about what brand to buy if I ever needed to top off.

Ron,

Sorry about wandering off your main coolant topic here. I, for one, did realise you had no present leak. But just in case one developed on the road...

The first link in my post right above yours, refers to a bewildering application and variety of Ford-family coolants. I would hope GM has not done the same thing. Assuming they haven't, the ideal add supply for you would be a %50/50% pre-mix water/Dexcool jug.

For the price of only one jug, this is what I would use if the need ever arose. Because they work hard, I do carry spare coolant in my tow trucks (I pre-mix w/distilled myself), and fully sympathize with your view.

Wes
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RJCorazza wrote:
As far as I am aware the Dexcool OATS coolants have not changed at all. Vehicle components and coolling systems (sealed / pressurized recovery tanks) were designed for Dexcool. You are correct that air and Dexcool are STILL a bad combination.
I believe the OP was discussing a leaking Dexcool filled cooling system. This is the beginning of a Dexcool sludge disaster.

OP here; just to clarify, no leaks are present. Was just wondering about what brand to buy if I ever needed to top off.

...

Larry,

Here is a Ford chart for Ford's recommended coolants.
https://www.fcsdchemicalsandlubricants.com/Main/quickref/scucEN.pdf

I don't have time to find the links now, but I remember reading that Ford failed to provide factory installed anti-cavitation additive in it's early International rendition diesels. They were not sleeved, but ordinary castings. Nobody at Ford knew about it and some early engines failed after high miles because of it. International supposedly provided the chemical in their own truck in the form of replaceable coolant filters, but Ford didn't use a filter to save money.

Ford has an additive, VC-8:
http://www.amazon.com/Genuine-Ford-VC-8-Cooling-Additive/dp/B000NU3LPS

More here:
http://www.ford-trucks.com/forums/1064454-check-coolant-additive.html

DieselManor has an add for such a supplement here:
http://www.dieselmanor.com/fleetguard/DCA60L.htm
Their reasoning is not what I understand it to be. My understanding is that the cavitation is caused by the diesel ignition accoustic shockwave that forms momentary rarifaction/compression in the coolant liquid next to the cast cylinder.

The following makes sense to me:
The cylinder actually slightly expands and contracts from combustion shock. This causes bubbles that collapse very violently, violently enough to minutely spall the metal (like a reverse windshield chip). Unlike a windshield with double layers, the cast iron eventually chips all the way through which causes pinhole leakage between the combustion and coolant. The additive merely coats the cast iron wall with a jell that softens the blow. It does seem logical to me that modern diesels with multiple injection can soften the initial blow enough to possibly be immune to the problem. The common observation is the reduced noise from a mild pre-ignition before full charge is injected; i.e. "quiet" diesels.

I'd be interested in links you may have that discuss cavitation more fully. There is apparently a lot of misunderstanding about the phenomena. I'll get back later when I have more time.

Wes
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As far as I am aware the Dexcool OATS coolants have not changed at all. Vehicle components and coolling systems (sealed / pressurized recovery tanks) were designed for Dexcool. You are correct that air and Dexcool are STILL a bad combination.
I believe the OP was discussing a leaking Dexcool filled cooling system. This is the beginning of a Dexcool sludge disaster.

RJCorazza wrote:
Most current Fords (2011+) use a dexcool type coolant, Ford spec WSS-M97B44-D (specialty orange). Zerex Dexcool is advertised as meeting the Ford spec. I agonized over flushing my 2011 F250 coolant and using G05 because of the Dexcool reputation, but after reading all I could find decided to stick with it. The problems I read about were component design and material related. The plastic/rubber seals and gaskets, non- pressurized recovery tanks, and cavitating water pumps.
Our 1998 pontiac was improperly designed for GM Dexcool (which I did flush out and replace with G05 in 2005). It was a gooey mess.

Interesting that Ford went back to the Dexcool type coolant in 2011 and IIRC the older stuff I referred to was in fact called "Specialty Orange" and has been around for at least 15 years. Re: the Dexcool reputation I think a lot of that had to do with some of the early formulations where the coolant if exposed to air and heat would "GELL UP" causing all sorts of issues. Not sure if that is still the case and the newer formulations might have had that issue resolved.

Larry

Most current Fords (2011+) use a dexcool type coolant, Ford spec WSS-M97B44-D (specialty orange). Zerex Dexcool is advertised as meeting the Ford spec. I agonized over flushing my 2011 F250 coolant and using G05 because of the Dexcool reputation, but after reading all I could find decided to stick with it. The problems I read about were component design and material related. The plastic/rubber seals and gaskets, non- pressurized recovery tanks, and cavitating water pumps.
Our 1998 pontiac was improperly designed for GM Dexcool (which I did flush out and replace with G05 in 2005). It was a gooey mess.

I won't comment on some of the "errors" I see in some of the posts, but will only make the following statements/observations for those interested. DISCLAIMER: I used to be fairly up to date on coolants, but haven't kept completely current for about the last 3 or 4 years so some of the following might have changed, but is sort of doubt it.

1. Be careful about buying and keeping extra coolant for topping off. IIRC coolants have a definite "shelf life" and it's only around 5 or so years and not "forever".

2. G05 and Dexcool are two VERY DIFFERENT COOLANTS. G05 is what Ford switched to in around 2005 and Chrysler/Cummins used to for quite a few years. I still believe Ford uses the G05 on both it's diesels and gassers and probably Chrysler for its gassers, but Cummins might have gone to one of the other ELCs. Ford did use a Dexcool type coolant in a couple of models, but they are only like one or two and that was like 10 years ago. Not sure if any FORD products currently uses a Dexcool type coolant now. Dexcool is a "STRAIGHT OAT" coolant whereas the G05 is a "HYBRID OAT".

3. Cavitation in Diesels is a very important consideration, but it is mainly in engines that have what is called a "wet sleive" technology where the cylinder is lined with a liner that has coolant in contact with it and this "thin" membrane provides a mechanism for the coolant to "cavitate" and eat away at the metal in that area. HOWEVER this cavitation consideration is almost non existant in the LD Cummins and Ford diesel engines since they use what is called a "parent bore" engine block that has no "liners". This results in VERY HEAVY cylinder wall to coolant passage interfaces causing coolant concerns to basically nonexistent.

Larry

Ford and GM both use Dexcool (last I checked, Dexcool happens to meet the same coolant specs that Ford specifies on their rides starting in 2011 or 2012). The odd-ball out is Chrysler/FCA, their OAT doesn't have some of the chemicals that appear in Dexcool compatible coolant. I believe it's 2-eha. Nothing on the market yet that's generic for FCA's coolant chemistry. Then the remainder of the europeans just have crazy different specs from mfr to mfr. Just a friendly heads-up for those that may think all long life coolants are the same.

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Coolant is a good thing to think about for our tow vehicles as winter approaches, so the OP is right on. Green ethylene glycol is deathly poisonous to ingest; friendly Dexcool not so much.

My wifes '95 Corvette had OEM Dexcool; so did her '00 Impala and my '94 Mazda. Dexcool worked fine as far as I am concerned and extended my service intervals.

The Dexcool only has to be changed out every 5 years as opposed to 3 years with green ethylene glycol. The LT1 Corvette had the waterpump go out, but that was because of dry seals from lack of driving. The waterpump bearing was still as tight as new when I pulled it. The rear pinion seal and clutch slave cylinder leaked too... garage queens typically have these sort of problems. Motorcoach owners with low driving time beware.

The Impala (3.4L) lost an intake gasket, but that period gasket defect happened to the majority of them no matter the coolant type. Gm also recommends that a couple of sealant pellets be added to all GM's as a matter of routine at the same time.

The Mazda (4.0L) cooling system survived unscathed, although it seems strange that the twin Ford Ranger... built on the exact same Ford line... got the green glycol stuff and a 3 year service interval instead of 5.

Probably the most overlooked coolant caveat are the diesel trucks. All require anti-cavitation additive, and Ford even recommends adding some in between coolant change-outs. Especially if the truck works hard (tuners note!), and doesn't have sufficient such additive, the cylinders can pit so bad from accoustic cavitation-spalling on the coolant side as to get pinholes leading from the waterjacket to inside the combustion cylinder.

Too much anti-cavitation additive is not good either, so it is recommended that the coolant be checked by a diesel shop lab equipped to do it. Locally that would be our Caterpillar dealer. Savvy pro-truckers use this service, as well as heavy equipment operators, as it is just as important as oil-lab checks if not moreso.

Wes
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majorgator wrote:

..I say to them, it doesn't overheat and doesn't leak and doesn't freeze up. I'm not going to fix something that's not broke.

It's not about fixing something, but rather maintaining what you already have. It's called preventative maintenance. Eventually all coolants will break down. Even long life versions. All you need is miles and time. Yes it's a sealed system, however the chemistry of the coolant isn't permanent. Rust inhibitors will deplete and the coolant will turn into a corrosive acid. This acid eats at the metal surfaces all throughout the cooling system. This isn't something that you can see unless you're going to scope your cooling system. By the time you see the leaks and overheating it's too late. You've suffered a high levels of metal loss and you're now replacing parts. At a minimum PH test your coolant to prove it still has life. That's something you can do yourself with strips. Ignorance may be bliss, but it can be pretty costly.