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HOAT coolant

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Soupy

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Gentleman: I want to change my coolant on my '03. I have John Deere equipment and use the JD premixed coolant. Does anyone know if this is a HOAT based coolant? If not, can one buy premixed HOAT coolant. Premixed saves us time at coolant changes and there is no make up water used.



Brian
 
Yes....maybe, check part numbers

Per this link it appears that the John Deere Coolant IS a HOAT (Hybrid organic acid technology). As far as its other additives being compatable with our engines, I am not certain. I personally used a Prestone product in a grey bottle, I arrived at this product after reading the bottles for an hour or so. I did a quick search of their website but did not see the same label/product. I am sure others will chime in to help you more.
 
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Chrysler says HOAT antifreeze must meet Chrysler spec MS-9769. If the spec is listed on the John Deere bottle you are okay. I sent John Deere and e-mail inquiring if it met the Chrysler spec. Have not heard back yet, but will post when they reply. I suspect the JD antifreeze would be okay to use either way though.
 
Thanks for the replies so far. I went and asked JD but no one had any idea what a Chrysler MS-9769 spec was or for that matter what HOAT stood for. IMHO, since JD approves of the G-05, I see no problem in using JD premix in my Cummins. I would like to see it on paper though but I am not holding my breath. I can find lots of specs for other coolants, but not JD per se unless of course it is the Zerex G-05.



Brian
 
If you flush and fill with new, you can use whatever you want. The Cummins repair facility in Fort Worth uses whatever the latest shipment might be on the pallet. They use what they have in stock. I have seen them sell Zerex regular stuff and Peak regular stuff. They use it in everything that comes through their shop.
 
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OK - a stupid question...



There frequently pop up questions on this board concerning various anti freeze brands and types as "approved" by Cummins. SO, what is so unique in regards to a Cummins - or ANY other non-sleeved parent-bore diesel engine that would require - or forbid - anti freeze used in OTHER common internal combustion engines? Cast Iron is cast iron, and the various other scattered components throughout the cooling system all seem pretty ordinary - so why any "special" anti freeze in a Cummins? And the bit about anti-cavitation compounds doesn't apply to these engines, either... ;)



Edumacate me! :-laf
 
Supposedly HOAT reduces aluminum corrosion. Radiator is aluminum, not sure what else. The 2003 service manual says HOAT is "recommended", so I guess that doesn't rule out use of non-HOAT antifreeze.
 
Supposedly HOAT reduces aluminum corrosion. Radiator is aluminum, not sure what else. The 2003 service manual says HOAT is "recommended", so I guess that doesn't rule out use of non-HOAT antifreeze.



ACTUALLY, the Cummins engine is used in MANY applications other than our Dodges - doubt all of them have aluminum radiators - and as I recall, the radiator in my '02 is brass with plastic end tanks...



Seems all the more common and popular brands of available anti freeze state pretty plainly they are good in ALL engines and metals - including aluminum heads and blocks...



Which is why I'm sorta curious as to why there would be a specific brand or type specified by Cummins in their engines. :)
 
I think the HOAT and aluminum radiators started with the 03's. I always used HOAT in my 03 and had no problems with the cooling system. May not have had any problems with regular antifreeze either, but it only cost $1 more per gallon for the Zerex G05.



I have always used regular Prestone in my 95 and see no reason to change.
 
How do we know that it is Cummins that specifies HOAT anti-freeze? The spec is found in Gen III HPCR truck owner's manuals. I would guess it is Dodge, not Cummins, who writes that spec unless MDTs or MHs w/Cummins ISB engines list the same requirement.

Auto-Zone stores carry Zerex branded HOAT anti-freeze that meets the Dodge spec.
 
Not to jump to far off track, but the old school Toyota Red anti freeze is prolly the best stuff ever made IMO. The 20R, 22R, and 22re all had Aluminum heads, cast blocks, and copper radiators. I had seen many posts and pictures with trucks that had 200,000 - 400,000 miles on their cooling systems and the insides of their radiators still looked new.
 
I think HBarlow is right. G-05 seems to be a Dodge spec, not Cummins. I like the G-05 though. I drained my system after about 4. 5 years and there didn't seem to be any rust like you usually see in the green stuff. The GM OAT formula seems to be much more available and probably gives similar corrosion protection but I haven't had a GM in a long time so I've never seen it in action.
 
I drained my system after about 4. 5 years and there didn't seem to be any rust like you usually see in the green stuff.



I drained the HOAT antifreeze in my '03 after 6 years :eek: and 37K miles. The drained coolant looked just as bright in color and clean as the Mopar G-05 antifreeze I poured back in. I used a flashlight to look at the inside of the radiator tank at the end of the core. It appeared like new. It must really be "extended life" coolant.



Bill
 
I had to change the water pump on my truck at 160K. My intention was to change all the hoses and antifreeze as well. I drained it and it looked very good, no visible clouding or impurities. So, like Bill Stockard, I put the old antifreeze back in and saved the new for later. I had bought G-05 to use as a replacement. I poured the old fluid through a paint filter and got a couple of bits of dirt from it. I didn't change out the hoses either.
 
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I drained the HOAT antifreeze in my '03 after 6 years :eek: and 37K miles. The drained coolant looked just as bright in color and clean as the Mopar G-05 antifreeze I poured back in. I used a flashlight to look at the inside of the radiator tank at the end of the core. It appeared like new. It must really be "extended life" coolant.

Bill

Bill,

I'm glad you posted that. I was already thinking of changing the coolant this coming winter like I did with the old '01 and '06 (not realizing it was long life) following the advice you gave me years ago to drain and replace what was drained annually.

I'll just leave this one alone for another three or four years.
 
I went round and round when I first purchased my dodge ctd about the coolant, it was low when I bought it so I went to the service manager and ask him to fill it to the proper level, and before he could write it up (yes he was gona make a ticket on it) I asked him, does the HOAT come in 50/50 blend... he said no, so I ask if he was just going to put it in full strength? he said they would dilute with water... I said you have deminerlized water? he said nope we use the hose kind! I said forget it and left and thats when I started my quest for info, after ten phone calls to different people and a few emails it seemed the HOAT made by Mopar or at least the name Mopar brand was the only one that met Dodges specs to the letter. also it has a darker orange color than the zerox has, and I didn't want to take a chance and change the color of the original fluid just in case it becomes a warrenty issue. It's terrible that these manufacturers has us dancing like fools to follow there rules of ingagement on everything we due to our trucks.



So I went back to dodge and bought the full strength HOAT and to the grocery store and bought some demineralized water and mixed my own.

I never had a clue what a pain it was to get that stuff in a 50/50 blend, and never did find it.

I know you can go to a cummins shop and get test strips to test your coolant to see if it's holding the right PH, which is really important to the life of the parts, and they also have the chemical to bring it back to the proper PH levels, Genos also sells the same stuff.
 
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I changed my factory coolant at five years/108,000 miles and it looked as clean and colorful as the new HOAT. If it is recommended, then its probably best to use it. Engineers, chemists and metallurgists do their jobs pretty well so i'll take their advice. A wise man learns from others mistakes, a dumb man learns from his own.
 
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