Date: Wed, 31 Dec 2003 05:56:35 GMT From: Bob <uctraingNOSPAMnopsamanet.com> Subject: Re: Saab Coolant
On Tue, 30 Dec 2003 14:18:33 -0500, cs <> wrote: >Bob, you got me looking when you mentioned the Dexcool and Zerex G05 >coolants. You caution the use of organic acid types, yet it appears >the Zerex is that type, per the following blurb on its site: "Utilizes >hybrid organic acid technology to minimize inhibitor depletion" Yes, it's a long story :-) The Dexcool and compatibles are a particular type of organic acid technology. There is a big difference between those and the G05 type of coolants. The problem is not so much with the org-acid but with the particular type of org-acid. They key to identifying the type (without an MSDS sheet) is to look for "long life" or "5 year life". Those are the controversial products. It appears that the problems with the long life org-acids like Dexcool are actually impurity related. In fact, some claim that Dexcool itself is the only issue and that other manufacturers products are better made. I've heard of some tests showing impurities in Dexcool right out of the drum. If you want a good scare, do a web search on "dexcool" and "corrosion" or some similar terms. There are thousands of pages on the problems. There's even at least one class action suit: http://www.cwcd.com/CM/ClassActions/ClassActions35.asp GM claims that the problems are only with radiators that are allowed to go low and pull air into the systems but their own documents show that they also have problems with sealers that are used in the factory, leftover solder, etc. >Query, do all green coolants contain high silicate content? I have >used generic Autozone and/or Napa green coolants for 15 years on my >'88 9KT, draining/filling it yearly, always using distilled water, and >water pump lube, w/o incident, though I have had to replace the water >pump twice (the last time being this year). Generally, yes. In fact, silicates are touted as a positive thing by Prestone. They revolutionized the industry when first introduced as a corrosion preventive. But, now we are supposed to be using low phosphate and low silicate. I don't know what was originally spec'ed for a 1988. Yearly changes would be a definite plus. THe only down side I see is that the high silicates cause water pump wear and some claim head gasket wear. The lube you are adding may offset that.