1985-1998 [Subscribe to Daily Digest] |
Coolant quality has no correlation at all to the manufacturer of the ethylene glycol. The specification for ethylene glycol is the same regardless of the manufacturer. The additives (antifoam, corrosion inhibitors) are what separates the wheat from the chaff.
The green stuff is the cheapest formulation. Prestone and other manufacturers stand by it as a quality product. It has the disadvantage that it contains silicates. In the presence of high mineral concentration, silicates can promote corrosion. Even when using distilled water, you will eventually end up with substantial mineral content in the coolant from the cooling system. I have also seen these coolants foam after being in service for several years.
The silicate-free coolants (Prestone long-life, DexCool, Saab, etc) are superior in that they contain a superior additive package and are silicate-free. These coolants were designed to meet the specifications of European car manufacturers. Regardless of what they claim, you still have to flush old coolant every two years. The long-life coolants widely manufactured today (Prestone, Havoline, Peak, etc.) are more compatible with other coolants than the DexCool formulations. Saab coolant in my opinion is a waste of money, it is the same spec as the other long-life (orange) coolants. Just costs more. You really have to like blue to spend more for the neat color.
MB coolant is similar in quality to the long-life coolants, with the added benefit of having pH buffers to minimize the effects of ethylene glycol degrading over time to form corrosive acids. Acids will destroy the passive (oxide) layer over time and result in severe corrosion- one of the reasons why coolant must be flushed regularly. Oddly enough, MB coolant contain silicates, it says so right on the label. There have been occasional postings on the 900 BB that MB coolant is a "life-time" coolant-that is pure hogwash. Flush every two years.
Incidently, I learned from a post on the 900 BB that Mercedes Benz no longer uses MB coolant in their new vehicles! They are using the European spec (orange) coolant in new MB cars.
The "environmentally friendly" coolants are propylene glycol based. They have markedly inferior heat transfer performance to the ethylene glycol coolants. I recommend you avoid propylene glycol based coolants.
The choice is yours. In any case, use distilled or mineral-free water to mix with the coolant. Personally, I use the orange stuff.
posted by 208.59.2...
, Sat, 19 Oct 2002 16:09:52, Sun, 20 Oct 2002 16:40:38
, Sat, 19 Oct 2002 12:19:04
, Fri, 18 Oct 2002 11:37:11
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
 |
 |
 |
 |
 |
