well I flushed it and it was dirty and stunk because it was old rad fluid with dexcool mixed. This van shouldn't have had it in it.. So I flushed it and it is like new..The crap in the rad fluid also was stop leak.. the bypass valve gasket above the water pump housing was leaking and somone stuck stop leak in instead of the gasket. LOL All is good thanx for all your replies Extra thanks to Mike Marlow
A couple links explaing Dexcool and sludge caused by faulty rad caps.
I have never been a fan of DexCool, as I know the chemistry and have tested those chemistries under laboratory and application conditions on a number of occasions.
Lack of silicate is a problem which is difficult to overcome in a coolant corrosion inhibitor package.
Silicate is there to protect aluminum surfaces.. It is probably better than most other additives, but is not an ideal inhibitor either. When it was left out of the formulation, problems started to happen.
Organic acid technology can reduce corrosion rates effectively, particularly over the short term. These are anionic compounds and often do not provide complete filming, especially when corrosion may be occuring at sites which do not respond well to anionic compounds. When this happens, pinholes or pitting may occur.
Organic acids are disabled by some dissolved minerals. Iron is one of the very most powerful precipitants of organic acids.
Moral..use what you want, or what you must use to keep your warranty valid. Modern technology is now compatible with DexCool, has some silicate in many cases, and is probably a far better type of product.
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