coolant for an 02 Legacy?

Although many folks do just fine with 'normal green glycol'-stuff, For close the same proce, low silicate might have a slight edge for our cars. I beleive the OEM is low silicate. Supposedly prevents impeller/other damage.

Carl

I have used Zerox G05 for the last 100,000 miles without an issue. If not G05 then Subaru OEM and don't forget to use Subaru's" Coolant System Conditioner" which is supposed to be used each coolant change.

I used to think silicates were abrasive, but apparently they're not in a solution with water. The real problem is that they don't stay in suspension forever and eventually form a gunky gel that can clog radiator passages. Traditional silicated coolant has a shelf life of about 18 months. Also - most Japanese cars have rather small radiators with small passages.

"The primary limiting factor in the shelf life of a coolant is silicate instability. Since silicate will eventually polymerize to silicate gel, all traditional coolants have a shelf life of about 18 months."

There are some corrosion inhibitors that are abrasive, like borates.

I thought most Japanese manufacturers specify a non-silicate formula with phosphate corrosion inhibitors. The main problem with phosphates is that they form crystals when mixed with hard water. So you've got this stuff floating around in the cooling system, and a good portion of the corrosion inhibitor is gone. The simple answer is to use distilled/deionized water.

So wet sanding never happens?

Sodium silicate is not sand. Sand (AKA silica) is silicon dioxide. The problem is that they sound similar.

thanks Carl and everyone else.

I'll look for low-silicate stuff, and compare the price against OEM Subaru coolant. I don't mind paying a few bucks more for the good stuff or the right stuff, it's just that I own an old truck (green stuff), a Beretta (green stuff), and a Trans Am (dexcool), so I'm already "stocking" two types of coolant... I'd rather not have to make that three. Don't even ask about oil... every car gets it's own thickness and some get regular, some get synthetic...

:)

Ray

Thanks!

You can use one of the "universal" coolants- Peak Global or Prestone All Makes All Models. I've used both in my WRX with no issues. Both are available in 50-50 premix form so you don't have to deal with obtaining distilled water and mixing it yourself.

Hi,

Regular Prestone or any of the other major "green" brands, mixed 50-50 with DISTILLED water, will do just fine. Change every two years at the outside. Change every year if you're a bit "cautious" or want your radiator to last a lot longer than most. Although most coolants on the shelf today say they're compatible with "any color," I'd stick w/ the older advice to avoid mixing Dex-cool types w/ conventional coolants.

All the silicate and phosphate talk generally has to do with undesireable side effects of mixing with HARD water. For the "measuring impaired," the "pre-mix" is convenient, though you're paying way too much for a half gallon of de-ionized water!

Add a package of Subaru's cooling system conditioner to help keep the head gaskets from leaking... and read up on bleeding all the air out of the system!

Rick

coolant?Hi,

The standard "yellow bottle" Prestone is a reformulated version. The label refers to it as "extended life" and "All Makes. All models". My best guess is that it is a Dex-Cool style coolant free of phosphates and silicates. The problem with old standbys is that the manufacturers are always changing their formulas. Prestone has probably changed their formula several times as they went from Union Carbide to First Brands to their current owner (Honeywell). There are still some traditional silicate/phosphate coolants like Peak and any number of lesser known or house brands. The new "Prestone Prime" may be closer to their traditional silicate/phosphate formula.

Silicates drop out regardless of the quality of water used. They drop out in the bottle even when unmixed.

Some people use a coolant exchange tool, which is recommended by Subaru for some models; I saw a service bulletin. Snap-On sells a few, which are powered off of shop air.

Sure. Sodium silicates (it's supposed to be a group of different compounds) are supposed to dissolve in water. I used to be under the impression that it was ground sand (silica) that scraped off corrosion, along with seals, etc. Apparently what it does is form a protective barrier on aluminum that reduces corrosion. Some automatic dishwasher detergent contains sodium silicates to coat dishes/glass and prevent abrasive damage in the wash. They seem to have come out of favor with the use of organic acid corrosion inhibitors, which are supposed to form a waxy surface on cooling system parts as a barrier against corrosion. They're also supposedly far more stable than silicates, with a shelf life of 8 years.

The links to Wikipedia entries refer to sodium silicates as "liquid glass". Apparently they will fuse under high heat (like an exhaust) and turn to glass.

Hi,

Close to 40 years ago, I had a car w/ a heating problem. The radiator shop diagnosed the problem as a leaking head gasket that wasn't quite bad enough to warrant replacement. The fellow told me to go to the pharmacy and get a bottle of sodium silicate, and gave me instructions for its use. It was supposed to find/ the leaks, and, as mentioned, turn into a glass-like substance that sealed them.

If I'm not mistaken, some of the products available at the auto parts store for sealing head gasket leaks still use sodium silicate. I'd have to go read a label...

Rick

"Water Glass" which is sodium silicate, used to be used to preserve eggs. Eggs could be submerged in the clear liquid and would stay fresh for extended periods, prior to the advent of refrigeration. It is also used as a heat resistant adhesive alone or with fibers and thickeners to adhere gasket materials to furnace and wood stove doors and assembly joints. Interesting stuff.

I have an 02 and was not part of the recall for the conditioner. How important is it? I didn't use it on my last coolant change and used Prestone. Thanks Jeff

I know this is an old topic, but I just drained and filled the coolant for my 2004 WRX last weekend. The following (need to click on the link for a copy of the article) has a thorough explanation of the different types of coolant being sold. I had thoughts of sending in a virgin sample of the Subaru Long Life coolant in for analysis, but I've since used up the bottle.

As far as what I didn - I didn't try and drain the engine block. There probably is a plug, but I didn't think it was that critical. I did make a small mistake where I didn't notice that the O- ring on the draincock had fallen off and dumped itself in the pan I used to collect the coolant. This was after I had "burped" the system. So I removed it with both radiator caps on. A small amount leaked out, but the vacuum actually held most of the coolant in like a finger covering the top of a straw. I burped it again, and I was set. The worst part of burping the system was that it would eventually overflow once the coolant heated up.

I'm not even that sure that burping the system is all that helpful with the WRX. It looks any air generally makes it to the high tank and it's pretty easy to fill that.

I'm not terribly convinced that there are dire consequences to mixing different types of coolant. Every manufacturer seems to have a different take on what's important.

If you read the label on Prestone's new "All Makes All Models" product in the yellow bottle, it's pretty much a Dex-Cool style coolant with the two standard OAT corrosion inhibitors. Prestone seems to be convinced that there are no immediate problems if mixed with any other kind of coolant. They said the same thing about their Dex-Cool labelled coolant in the silver bottle, for what it's worth.

so which did you use?

Subaru Long Life. It was about $14 at a dealer in Carson City, Nevada where I saw the dealer driving between Reno and Tahoe. I don't know how much it would closer to home. One local Subaru dealer doesn't even stock the stuff. They also sell Fords and use/sell the green Ford standard coolant for Subarus.

I have used Zerox G05 with great success for about 5 years. If you don't go with OEM then go G05

Zerex?