Does antifreeze type matter?

I know there are differnt types of oils, and transmission fluids. Are all antifreezes the same? I know there is the 50/50 type and gallon jugs of straight antifreeze. Within those types are there different types? How do you know which type is best for your car? Presently I am using straight antifreeze that I then take and pour half into another jug and then add water to both giving a 50/50 mix.

Yes, type (but not brand) does matter. “Type” refers more to the antifreeze’s specific chemical components and additives, not so much whether or not it is pre-mixed. Your owner’s manual will tell you exactly what type to use, and if you don’t have the manual a simple google search for your car and “antifreeze type” should yield the correct info.

Yes, antifreeze type matters. Your owner’s manual will tell you which type to use in your Taurus.

You can buy premixed (50/50) or mix it yourself, but that’s not what’s important. The type and color of the antifreeze are what matters, and you can’t mix types together.

Well I just had to have a brand new radiator installed in my car. Before the replacement I had green, after the replacement they put in green so I have stayed with the green. I didn’t know the different colors ment anything but now do. I keep a gallon of 50/50 green in my car so I guess I am okay. It was the generic from Wal Mart that I bought.

Yes, like they said, type matters. I never realized how messed up this whole antifreeze type problem is, until someone posted a link to the Ford antifreeze help page. Ford, BY ITSELF, has used a number of different types. What in the world is going on here? How much difference can there be? I don’t understand why this couldn’t easily be standardized, much more easily, than, say, oil…

I would stay away from anything with DEX-COOL (GM) on it, unless your new car came with it. Then you have to use only that type.

I just knew that someone would badmouth Dex-Cool as I moved down this post. We have owned several late model GM cars that used Dex-Cool beginning with a 1996 driven to 135,000 miles and never had a problem. Our 03 was driven to 71,000 miles. You must keep a good radiator cap that does not leak; easy for me as I never had to replace one with Dex-Cool and for 6 year changes use a compatible antifreeze as per the label on the bottle which is much easier to do now as the industry seems to have caught up.

Make something new and improved and some dummy will screw it up if things are not exactly as they were before.

Dex-Cool problems are infrequently mentioned now on Car Talk.

Well, I had my car coolant changed and the garage put DEX-COOL in my Nissan, and it ate up the radiator in short order after being topped up with a noraml “antifreeze”. My emphasis was to stay with DEX-COOL if you already have it and not to switch to it if you dont’ due to the INCOMPATIBILITY.

My new Toyota calls for a special Toyoata coolant of whcih I have a spare jug for topping up!

Some things are very reactive in combination. If you drink alcohol and breathe in Carbon Tetrachloride, a common cleaning agent for fabrics, you will be dead in very short order. Both substances have their useful roles in society.

Many, many mechanics have replaced a whole lot of intake and head gaskets on late model GM cars, and the problem is usually caused by Dex Cool reacting over time with the gasket material. You’ve been one of the lucky ones to not experience this problem. There have been way too many examples of the same problem to attribute it all to poor maintenance on the part of the car owners.

Mr. Docnick,

Your mechanic should obviously not have mixed Dex-Cool with your Nissan antifreeze. For that error on the part of your mechanic, you should not denigrate Dex-Cool but should instead, point out what is required. Another way of looking at it is that the residual Nissan antifreeze in your engine may be at fault. Who would have known that and it is an unfortunate thing. GM is not responsible for Nissan products. Historically antifreeze brands have been uniformly compatible but instructions on the bottle must be read.

DexCool is fine. As long as the vehicle owner maintains the coolant level there’s no problem. But, if air gets entrained in the cooling system over an extended period of time it turns the DexCool acidic. And that’s when the sludging of the coolindg system happens and gaskets erode.

You have to remember. DexCool claims it CAN go 5 years/150,000 miles. Nowhere do they claim it WILL go 5 years/150,000. And that’s where the owners of vehicles with Dexcool get screwed. Because once they realize it CAN’T go 5 years/150,000 miles, the damage’s done.


I put Dexcool in my Nissan, left it there for 7 years will no ill effects. It now has the Universal type in it.

I just knew that someone would badmouth Dex-Cool as I moved down this post.

Telling someone not to use GM’s Dex-Cool coolant in a Ford isn’t badmouthing Dex-Cool. He didn’t badmouth it at all. He simply gave the OP some good advice.

Maybe you should let go of that Dex-Cool chip on your shoulder.

The materials used in car cooling systems and engines has changed a lot in recent decades. Coolant chemistry has changed to match them and to increase the service interval. I could go into the different approaches to corrosion inhibitors, silicate, phosphate, organic acids,…, what am I forgetting?

Unless you are a chemist or engineer with knowledge of corrosion, why second guess the manufacturer? Look here. What year is your Taurus? Go get some Zerex green or G05. The dealer’s prices are way too high, generally.

Ford’s departure from the old green stuff is probably to get away from silicate corrosion inhibitors which tend to polymerize (gel) excessively after a couple of years. What the new DG stuff is, I don’t know. We should assume it is an improvement since it comes a full decade after the last change that Ford introduced in 1999. The orange stuff may have been an experiment in the Cougar. The Transit Connect is a Euro vehicle brought over here so it might not be tested with Ford’s more common coolants. I believe that their orange stuff is Deathcool by another name, but don’t take that to heart.

As Beadsandbeads states (or not really quite stating it this way) the movement toward the OAT AND HOAT newer antifreeze products were to reduce incidents of required service. In the case of Dexcool (and other types of its composition) there’s always the universal law of the other shoe dropping. While it was fine for the spec’d interval …it assumed 100% system integrity to be viable. Get some air in the system …then the side effects were WORSE than the alternative and obsolete 3year/36000 mile former standard with green.

All evolutions are to move the first service on just about everything except oil changes beyond the first ownership cycle. For some it turns them into (sorta) “throw away” cars. Pay them off and trade them in.

There’s no restrictions that I’m aware of for material compatibility of any OTC antifreeze and any engine. That DID NOT mean MIXING of dissimilar coolants . The rest of the deal is frequency of service requirements. The high use of mixed alloys makes cooling system maintenance much more important than it used to be.

I don’t use any OEM spec’d fluid. I use Low Tox a propyleneglycol blend. I’ll service it every 3 years. Some will caution you to not attempt to out think the engineers …but as we can see from Dexcool and potential unintended consequences …they aren’t infallible and often don’t think on the secondary or tertiary level in terms of impacts.

To ground the football for yardage is a violation
To ground the football for time is not.

That is, just throwing in green and thinking that it’s good for the same duration as the more expensive and spec’d fluid is unwise.

Eliminating the factors that make it required is not (changing it out like you should - which many people failed to do - hence the alleged idiot proof fluids).

Yes, that’s the chart I remember. What’s with the switch to ‘dark green’ coolant for some, but not all, of the cars, sometimes mid-year?

Why can’t it. I went 5.5 years and 150k miles with it in my Saturn. Then I changed to the “universal type”. Now at over 200k, no problems.

DEX-COOL’s main problem is its incompatibility with other coolants. It cools fine as intended otherwise. The tech who mixed mine up was working for a reputable independent repair shop, and probably forgot this important fact. The shop redid the repair for almost free!

I’m not conderned with the eating up of intake manifold gaskets anymore although that happened on my Caprice; not sure if it was the gasket itself or the DEX-COOL.

Anyway it’s irresponsible to recommend this stuff to amateur mechanics in view of the damage that may result from mixing it woth other coolants.

Hence my post; if you already have it, keep using it. If you don’t have it, don’t choose it!

Engine coolants, like engine oils, should all be compatible.