anti freeze

I'm using an Australian-made coolant from Nulon (at "

") which is supplied in concentrate form and mixedwith the appropriate quantity of water to form cooland-fortified watermixture.

The local supermarkets sell highly-diluted coolant in 5 litre containers, but they're all around 25 percent of less of coolant in the mixture.

Some people seem to believe that the best way to use coolant additives is mix them 1:1 with water - has anyone tried that with Saab 8V or 16V engines in 900's?

Regards,

Craig.

I don't even remember what I put in my 89 c900s years ago. And I don't keep track of what I pour in the cooling system of all three of my

9000's. Got the anti-freeze from Pepboys.

IIRC, the '93 had Saab Blue G48 as factory fill. The Mercedes or Zerex G05 coolant (labeled for Daimler Chrysler/Ford) is similar and is what I would suggest. These 2 coolants give better protection especially in view of the engine construction (Fe/Al). If you want to use the Saab coolant, go ahead. If you use the G05, it'll similar protection and is easier/cheaper to find. Green stuff is similar (basically any standard coolant) in makeup, but is not as well buffered and should be changed more often. DexCool should be avoided like the plague in any car regardless of factory fill.

KeithG YMMV, $0.02

Mac Townsend wrote:

I have *no idea* what Prestone brand is.

All modern coolant additives are designed to be used in mixed steel / aluminium engines.

I just buy the cheapest stuff my local motor factor stocks. Works fine. There's nothing new about this.

Don't worry about it.

Graham

Nonsense.

BTW - flush your cooling system ( with plain water ), preferably several times, before replenishing to get any shit out of it..

Graham

Ummm. That's what I've *always* done. A 50/50 mix of antifreeze and water is what is generally prescribed for best freeze protection and maximum anti-corrosion.

-Fred W

SAAB antifreeze is Glysantin G-48. Mercedes antifreeze is either the same exact stuff (if blue) or Glysantin G-30 (red color). They are almost the same, but I would go with G-48. Glysantin is the trade name for antifreeze made by BASF. They produce and repackage the stuff for most of the major car manufacturers. For example G-48, in addition to being sold in a SAAB package is also sold as BMW, Jaguar and VW brand antifreeze.

*CW

NO!! They do not.

There is a big difference between the "green stuff" (Prestone, regular Zerex, etc.) and the blue stuff. Have you ever dismantled cooling system componments and noticed a scaley white crust coating all of the aluminum parts? Those are the minerals (silicate, phosphates, etc) that came from that green stuff. When you use *only* the blue stuff and pull off your waterpump some day, you will notice there are none of these deposits.

Zerex does market Glysantin as well, so you may be able to find either G-05 (yellow), G-48 (blue)or G-30 (red) in a Zerex package a the store, but it will be clearly identified with the G-# on the label. Any of those would be OK and preferrable to the dreaded green stuff.

Also, stay away from the Dexcool (orange) stuff as that is highly acidic and not at all recomended for SAAB engines.

-Fred W

Well summarized Fred. There is a big difference in coolant these days. I spent a _lot_ of time learning about coolants last year. Companies like Prestone (who only sell green/high-silicate and Dex/carbox) do not acknowledge the differences because they don't have low silicate and/or low phosphate products to offer. Levels of silicate and phosphates vary widely in different mixes, as well as whatever is used to replace them as corrosion inhibitors if they are not there in high levels (and often not wanted in high levels).

Avoid the green stuff. The silicate (abrasive) levels are way too high. Avoid Dexcool, contamination problems are serious and common. You can't buy G48 as far as I know in the US in less that 55 gal drums except as Mercedes coolant. You can buy Zerex G05 at any Autozone store (in the USA). Look for the gold bottles. Or, you can just buy Saab coolant - at my local dealer, it costs about $1 more than Zerex G05.

Yes, there is.

Bad advice.

Thanks, Fred.

I had a chat with the folks at the shop where my head gasket is currently being replaced

There is some difference of opionion between Toyota/Japanese Mfrs and the Euro Mfgrs. Toyota seems less concerned about phospates but inisits on low silicates while Euto wants minimal phosphates and doesn't care as much about silicates. They stock BMW and Mercedes brands, but suggested looking for the proper (low phosphate) Zerex or Quaker State at AutoZone/ whatever ...and thanks to your missive (and those of others), I will know a little better exactly what to look for.

First, some background: in the 70's prestone invented the high silicate" type of green stuff. Silicates help prevent corrosion. It was considered a major advance in that area. However, silicates also cause wear (silicates are abrasives).

Japanese cars are famous for wearing out water pumps. Many feel that the silicates in some antifreezes are the culprit. I've seen some evidence but nothing clinical. It may be Japanese manufacturing that creates water pumps that wear easily, I don't know. I do know that Nissan and Japanese dealers are stringent on the requirements for non silicate AF.

European manufacturers worry more about phosphates. They don't seem to have the Japanese water pump problems. I can't say why. I've also heard that European water supplies are more likely to be higher in minerals that add to the phosphate problem, but I have no real info on that. Could just be rumor. Whatever, all the Euro manufacturers worry about phosphates and _low_, not _no_ silicates.

Zerex (G05) is low phosphate, low (not "no") silicate.

Care to advise ?

Graham

Fred's message covered it very well. Your information is a decade out of date.

So going on what you and Fred have said, it's best to go with blue-coloured coolant (G-48 apparently? Not sure what that actually means) for the lower mineral content than common green and red-tinted coolants? My 900i doesn't appear to have anything added to the water in it's cooling system, which is why I'm interested as I want to flush the cooling system and re-fill it with the right mixture.

I've never seen either blue or yellow coolants in local supermarkets (they do have green though - the Nulon green-coloured concentrate I mentioned in a previous posting was sourced that way), but I wonder if the local auto-parts store will carry more exotic coolants...

Regards,

Craig.

In the UK, it is very hard to find off the shelf an anti freeze that isn't ethylene glycol based with corrosion inhibitors. they are all pretty much 3 makes of AF dyed and badged for 30 companies.

Only dealer branded stuff is any different, but still ethylene glycol based. It's rare to find alchohol based anti-freeze or non corrosion protected mixes.

Sorry skodapilot, but you are really off-base on this one.

Yes, almost all antifreeze marketed is EG based, but there are some PG (Propylene Glycol) based ones out there that claim to be more environmentally friendly. I'm pretty sure alcohol as an antifreeze is obsolete.

Also, the EG based antifreezes are *not* all alike with differing corrosion inhibitors. They are considerably different in their chemical make up. If you intend on maintaining and keeping a car for a long time, it is in your best interest to buy and use the good stuff. Yes the price may be double ($10 a gallon instead of $5) but that price is negligible compared to the potential damage caused by a buggered up cooling system.

I would recommend that anyone (especially SAAB owners) read the excellent information and advice on Tom Townsend's SaabMaster technical website. Go to the cooling section and you will find a lot of good info about his experience and observations with a metric buttload of other peoples cars and the cars he has cared for over the years.

The site is at: but it is hosted at a dynamic IP address and seems to only work off and on.

-Fred W