Coolant compatibility

[JLovas]

Just stopped buy the dealer to get a gallon of antifreeze for my pickup (she's seeping a little from the block heater). I told them what I needed and walked out with a gallon of ethylene glycol coolant (Mopar part # 05066386AA). Owners manual states "This vehicle has not been designed for use with Propylene Glycol Based coolants", and states that I'm suppose to use a Formula HOAT P/N 5011764AB I'm not much of a chemists, so can you folks tell me if the coolant I bought is suitable to top off my overflow tank? Thanks

 

[GerryDrake]

Antifreeze

When I noticed my block heater was leaking coolant, I bought a gallon at a dealer in Texas, and they looked it up and sold me the same part # you bought. It has MS-9769 and Embittered on the label, whatever those mean. At any rate, I also bought a gallon of distilled water, and put about a quart of each in (50/50 mix) to top off the overflow reservoir. It is the same orange color, and appears to be the right stuff. I suspect that number is a new number for the other number, but would rely on someone like Tomeygun to confirm that. Later, when we were home, took the truck to the local dealer for a couple very minor warranty items, including having them tighten the block heater to stop the leak there. That has been a very common problem over the past several years' models... Mine doesn't leak any longer, and the added antifreeze was about 19K / 26 months ago. I think we have the right stuff, but will be interested what Tomeygun says... Gerry

 

[rbattelle]

HOAT coolant (which stands for Hybrid Organic Additive Technology) is itself an ethylene-glycol based coolant. Therefore, it should be compatible with any ethylene-glycol coolant, even if it's not HOAT. I did quite a bit of research on HOAT before I changed my coolant out, and I found the HOAT is pretty much compatible with everything out there, so don't worry about gelling issues or anything like that. You should have no problems.



As you point out, the owners manual specifically forbids the use of propylene glycol. When I had my coolant changed out, they put PG in it (Fleetguard Compleat Premix). That was almost 2 years ago now and I've not had one bit of cooling system trouble. I'm not sure why they don't recommend PG, unless maybe PG is incompatible with HOAT and they don't want you messing things up.



-Ryan

 

[MBergman]

You bought the right coolant. The 5011764aa was the old part number for pink HOAT stuff. It superceded a few years ago to the 5066386aa. Nice of them to not change the part number in the owner's manuals. Mopar only uses the pink HOAT and the normal green ethylene glycol (4267020ab). I would not recommend mixing the pink and green together. They become corrosive to the cooling system.



Marc

 

[JLovas]

Thanks for the information guys, its appreciated. I trust the collective knowledge of the TDR a lot more than any local dealer.

 

[rbattelle]

I would not recommend mixing the pink and green together. They become corrosive to the cooling system.

I don't quite understand this chemically. If the "green stuff" is ethylene-glycol based, and the "pink stuff" is also ethylene glycol based, then what specifically is in the additive packages that would cause corrosion issues within the cooling system? And are you talking corrosion of the aluminum parts or the iron parts? I find it very odd that any mixture of any coolant on the market could result in a corrosive mixture.



Could you clarify a bit?



-Ryan

 

[MBergman]

I've seen a few cars go through the dealership with them mixed together. The water pump seal, heater core, timing cover (aluminum), and radiator seem to be affected the most. I'll see if I can dig up more info on it.



If the system is completely flushed, it seems to be ok. Just avoid mixing the pink and green together.



Marc

 

[MMeier]

Just get rid of the pink colored stuff and use good ol' Prestone!!

 

[Tony T.]

I don't quite understand this chemically. If the "green stuff" is ethylene-glycol based, and the "pink stuff" is also ethylene glycol based, then what specifically is in the additive packages that would cause corrosion issues within the cooling system? And are you talking corrosion of the aluminum parts or the iron parts? I find it very odd that any mixture of any coolant on the market could result in a corrosive mixture.



Could you clarify a bit?



-Ryan

I tend to agree with Ryan on this also, a little dazed and confused myself with both being eg based af/coolant, but just different dye colors that I understood. Looks to me maybe a marketing thing more than anything. Really this antifreeze/coolant mess is confusing at times,why not just use one dang color and additive package for all vehicles so then each person can choose their favorite blue,yellow,orange,etc color container with their favorite product name that it comes in.



Also I have noticed the Walmart I usually visit, the last serveral times I have not seen the Zerex G-05 (HOAT compatiable) antifreeze/coolant available, like they pulled it from the shelves. All I find now is Prestone and Super Tech antifreeze/coolant whats the deal with that. I have ask back in service dept and get the blank stare, along with I don't know, what we have available is there on the shelves. Thanks alot.



Tony

 

[rbattelle]

Also I have noticed the Walmart I usually visit, the last serveral times I have not seen the Zerex G-05 (HOAT compatiable) antifreeze/coolant available, like they pulled it from the shelves.

Hey Tony, haven't "seen" you around in awhile! Nice to see you're still here.



This is one reason I wanted to switch over to a standardized (ie. , readily available) PG or EG coolant. I was afraid availability of HOAT would be troublesome. However, it seems that manufacturers have embraced HOAT (I know DC and Ford are both using the same stuff, just different colors), although the imports don't appear to be using it (Honda, for example, uses a formulation entirely different from HOAT). Nevertheless, I've seen Zerex G-05 at most auto parts stores, so I'm not sure why Wal-Mart would stop carrying it. I certainly hope it's not a case that it's going to get very scarce.



I changed mine out also because I got spooked by the whole Dexcool debacle. I mean, we know that traditional EG or PG formulations work well, so why mess with things?



-Ryan

 

[Tony T.]

I've just noticed the Zerex G-05 missing from this one particular Walmart I go to, it may be different at other Walmarts, I don't know they may still carry it. I had planned on using it when the time came to change af/coolant. I may end up using the dealership stuff since I have a friend in parts that gives me a discount on parts if the price is comparable.



Yeah! Ryan I still lurk in the shadows.



Tony