Mixing coolant colors?

My wifes car manual states to use blue Nissan compliant coolant.

Coolant is a bit low, is mixing in univeral coolant that says any color, any make/model but its of a different color fine?

Im assuming Nissan just wants you to buy their stuff.

There are big differences in types of coolant these days. I would spend the extra to buy the Nissan stuff as cheap insurace. I only use the universal stuff if doing a complete change.

If its just a little bit you can add some distilled water, otherwise go to Nissan.

It's not the color so much as the composition. There's low this and high that and EOAT and GOAT and BOAT and I don't know what else. I have charts to remember it for me, but I never look at them because "use OE coollant" is easy to remember. Some types are massively incompatible with others.

The "universal" coolants are universal because they don't have any of the fancy additives in them that can cause incompatibility. They are water and ethylene glycol and some minor anti-corrosives since water is corrosive and ethylene glycol, pure, is heavily corrosive. It relies on the additive package from the remaining coolant to work. It's sort of like transfusing plasma instead of whole blood (imperfect analogy but it works well enough).

You can top up with "universal" coolant but you really should use the OE stuff for a flush and fill, in other words.

Dump some Peak Global in there and forget about it, though unless it's still under warranty it's probably due for a change (5yr/150k) anyways.

Thanks, had knee surgery so fell behind on car maintance.

Actualy had my wife in my garage jumpsuit doing all the on the ground work for oil changes on our cars.

Now that I'm somewhat better a coolant flush and fill is on my to do list for her car as it just hit 5 years 120k miles. Just needed to get it through another 4-6 weeks.

I think the big thing to do is not mix iat (inorganic) with oat (organic), doing so iirc can cause your system to gel or cause some other problem.

Iat will most likely mention things like phosphates and silicone inhibitors while oat will not. Another thing is that iat coolant should be changed every 2-3 years to prevent internal damage to your cooling system. Most of us probably don't and the cars will usually die of other things, not a cooling problem. Small impact imo

Again iirc oat also have global ratings g-5, g-11 etc meaning there are different types of oat within the General category. It's best to stick with one but it's not the end of the world as long as it's good enough for your car.

I'd grab your specific Nissan coolant if you can otherwise most Japanese cars have been using oat since the 90's and 00's. Double check what you got and good luck

Toss in some water.

IMO, if you're not 100% sure the coolant chemistry is the same or at least compatible, don't mix them. That's how you end up with a system full of brown sludge.

And if you change coolant types, flush the system really well (and make sure the stuff going in doesn't have any issues with metals or gaskets in the system). As a note, any system that uses old school green will take G-05 safely if flushed well (G-05 is the same as the gold Ford stuff or the pink Mopar stuff).

Also, the Prestone "all makes all models" stuff and most other universal coolants are just Dex-cool that isn't orange. A few like Peak Global Lifetime exclude the 2-EHA that can eat some gaskets, but they still shouldn't be mixed with other types of coolant.

Just don't mix red and white. You're sure to be marooned.

Umm, maybe I should bump up the priority on the full system flush.

Ok, stupid question then, just replaced the radiator on the NB ('00), and flushed it and ran Peak something or other (50/50 mix, I'm lazy) - do I need to swap that out for "OE" type?

OldGray320i wrote: Ok, stupid question then, just replaced the radiator on the NB ('00), and flushed it and ran Peak something or other (50/50 mix, I'm lazy) - do I need to swap that out for "OE" type?

OE coolant on NBs is the generic green ethylene glycol stuff. :)

+1 on the distilled water idea. If you only need to add a cup or two, distilled water to dilute it a bit more is fine. Just don't do it every month.

codrus wrote:

OldGray320i wrote: Ok, stupid question then, just replaced the radiator on the NB ('00), and flushed it and ran Peak something or other (50/50 mix, I'm lazy) - do I need to swap that out for "OE" type?

OE coolant on NBs is the generic green ethylene glycol stuff. :)

Thanks, I feel better.

These newfangled horseless carriages have me confused sometimes about what I'm supposed to give them... except for tossing hay bales, hay and water was easier.

Next problem, I put hay in it's mouth, but it seems hesitant to get up and go.....

In reply to codrus:

It's all ethylene glycol, it's what else is in there that makes mixing an issue, though from what I understand anything other than old Dexccol and "tradional"/"old school" high silicate green stuff is kosher. The "long life" chemistries are all pretty similar, most of the "mixes with everything" stuff is basically improved dexcool. Much like the oil argument the more important thing is to change it on the correct interval.

TurboFocus wrote: I think the big thing to do is not mix iat (inorganic) with oat (organic), doing so iirc can cause your system to gel or cause some other problem. Iat will most likely mention things like phosphates and silicone inhibitors while oat will not. Another thing is that iat coolant should be changed every 2-3 years to prevent internal damage to your cooling system. Most of us probably don't and the cars will usually die of other things, not a cooling problem. Small impact imo Again iirc oat also have global ratings g-5, g-11 etc meaning there are different types of oat within the General category. It's best to stick with one but it's not the end of the world as long as it's good enough for your car. I'd grab your specific Nissan coolant if you can otherwise most Japanese cars have been using oat since the 90's and 00's. Double check what you got and good luck

There's also the Hybrids which are IAT's mixed with Organic inhibitors. Most automotive grade coolants will be either straight conventional with minimal inhibitor packs or hybrids. The biggest issues typically come in larger engines that go with extended drains.

I can tell you that analyzing coolants sucks. Every fluid manufacturer does their own thing, no one knows what they have and it's always mixed.