Originally Posted By: skyship
Boron compounds can combine with water and fall out of solution, in a gearbox that is contaminated with water it forms sludge, but it should get caught in the engine oil filter I presume.
The detergents and anti wear additives shown in a UOA are not necessarily still active, so the figure is not of great interest although it does give you an idea what was in the oil when new. The Calcium figure increases slightly due to evapouration of base stock components.
You're correct and I agree with you about the reaction with water regarding Boron compounds. In transmissions, where Boron based dispersants are used, the reaction with water creates 2 scenarios.
i) the drop out that you describe
ii) there is the reaction with water that creates boric acid, which I think someone else has also described.
The danger here that exists and is current in the market place is that the Boric Acid (under certain conditions) can crystalise and the crystals are able to get into valve bodies and cause them to jam, thus creating a transmission failure. You can find evidence of this if you take a look at warranty claims from a certain European OEM related to their activities particularly in China. There are both Television Reports and also Newspaper Articles pertaining to this failure mode.