Mixing Antifreeze Types

[C.Amick]

I know in automobiles you are not supposed to mix the old ethylene glycol with the new type coolant. Most of my antique tractors still have the ethylene glycol coolant. Does it hurt anything to mix the new type coolant with it in old tractors?

 

[JDIH]

My experience is that mixing dexcool with old style green it makes a muddy sludge that builds up. Theres many different types of coolant out there now. Most vehicle manufacturers have their own. I dont know how other types react

 

[Janicholson]

To refresh to a 50 50 mix, using the old green stuff is way less risky then potential clogging. The green stuff is readily available. If complete change is done, no issue. Jim

 

[old]

From what I have been told by people like the Manager of O'Reilly's who was an auto mechanic and had his own shop is if you ix them they make a gel sort of stuff and then the only way to fix that is to do a total rebuild and it does not matter what engine you have

 

[rustred]

keep with one or the other type. why mix it. so much stuff out there now hard to keep track.

 

[Steve@Advance]

I agree, it's the Dexcool that doesn't like to mix with anything.

There are "universal" formulas that are supposed to be safe to mix with other types, but I don't think that applies to Dexcool, the red stuff.

I still prefer not to mix any of them with an aluminum radiator or aluminum castings, and for sure not with high tech diesels!

 

[caterpillar guy]

I just use the green stuff in everything no mix ups that way. Works in everything also. In the late 90's early 2000's they had trouble with some of that new extended life stuff with gaskets. Made me stay away from it.

 

[MarkB_MI]

First off, almost all antifreeze is ethylene glycol, although there is at least one non-toxic propylene glycol antifreeze available, <a href="https://www.peakhd.com/product/automotive-antifreeze/sierra-propylene-glycol-antifreeze/">Sierra</a>. Although Sierra has been on the market for decades, it has never really taken off.

The difference between antifreeze types is the additive mix. Traditional (typically green) antifreeze is now called "non-organic additive technology" (NOAT) and the newer stuff is called "organic additive technology" (OAT). There are also variations that mix non-organic and organic additives.

In general, it's best not to mix additive types, but it's not the end of the world if you do. The main problem with adding old school antifreeze to newer stuff (such as Dex-Cool) is that it tends to reduce the long life of the OAT antifreeze to that of NOAT. I keep both NOAT Prestone and OAT Dex-Cool on hand; the Prestone goes into my tractor and the Dex-Cool goes into my various GM vehicles. There is really no concrete evidence that mixing antifreeze types causes problems (such as sludge), but it's not that big of a deal to keep both types on hand.

 

[Sprint 6]

Not going to hurt anything. I only keep a 55 gallon drum of Napa Long Life all makes coolant concentrate. It is yellow and mixes fine with anything. Been using it for 10 years with no issues. The only thing I buy specialty coolant for is hybrid inverter cooling systems, I buy premixed in whatever color the vehicle uses.

 

[Hobo,NC]

(quoted from post at 16:47:31 08/24/20) Not going to hurt anything. I only keep a 55 gallon drum of Napa Long Life all makes coolant concentrate. It is yellow and mixes fine with anything. Been using it for 10 years with no issues. The only thing I buy specialty coolant for is hybrid inverter cooling systems, I buy premixed in whatever color the vehicle uses.

About the same here unless its still under factory warranty.
Diesels get factory fluid exclusively...

 

[Stephen Newell]

A lot depends on what different antifreeze. The new antifreeze is the same thing except it has an additive to make it taste bad to animals. Now mixing antifreeze of different colors shouldn't be done. That can cause damage to the cooling system of the vehicle. The different color tells it's a different type antifreeze. Better to drain the old out and flush it than to mix different types of antifreeze.

 

[buickanddeere]

Not saving anything mixing the old coolant with expired corrosion inhibitors with new coolant .
When mixing new coolant . Use distilled water instead tap water . Why pour lime and calcium into the cooling system ?

 

[sotxbill]

(quoted from post at 05:16:03 08/24/20) First off, almost all antifreeze is ethylene glycol, although there is at least one non-toxic propylene glycol antifreeze available, &lt;a href="https://www.peakhd.com/product/automotive-antifreeze/sierra-propylene-glycol-antifreeze/"&gt;Sierra&lt;/a&gt;. Although Sierra has been on the market for decades, it has never really taken off.

The difference between antifreeze types is the additive mix. Traditional (typically green) antifreeze is now called "non-organic additive technology" (NOAT) and the newer stuff is called "organic additive technology" (OAT). There are also variations that mix non-organic and organic additives.

In general, it's best not to mix additive types, but it's not the end of the world if you do. The main problem with adding old school antifreeze to newer stuff (such as Dex-Cool) is that it tends to reduce the long life of the OAT antifreeze to that of NOAT. I keep both NOAT Prestone and OAT Dex-Cool on hand; the Prestone goes into my tractor and the Dex-Cool goes into my various GM vehicles. There is really no concrete evidence that mixing antifreeze types causes problems (such as sludge), but it's not that big of a deal to keep both types on hand.

noat, oat and moat...

euro cars call for Moat, modified organic additive technology.

 

[the tractor vet]

This antifreeze thing any more makes my head hurt , ya have the Green , ya got the Orange , Ya got the yellow and ya got the Purple . And shame on you if you get the wrong color in the wrong piece . That THING they call a CAR takes the purple , the old Druango takes the Orange , the one ton takes the green , the old Sebring take the yellow . But Some one put the wrong stuff in the REVENGER and yep it plugged the heater core and was also causing a slight over heating problem on warm days and not getting up to temp on cold days . Well not being up on this new fangled stuff and still had some factory warranty left i sent it off to the goat store and the OLD service manager enlightened me , so they did a flush and installed the TWo T stats that it has ( never heard of such a thing ) . BUT we still did not have much heat and the one day i was checking the engine oil i noticed that WHAT it still has the ORANGE juice in it and NOT THE PURPLE and had to take it back for a redo . But still had a plugged heater core.

 

[moresmoke]

Typically the universal antifreeze contains no corrosion inhibitors. It is just ethylene glycol and water.

 

[Rollie NE PA]

Don't forget HOAT (Hybrid Organic Acid Technology) used in Mopar vehicles. Expensive stuff>