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Assembly without all the pieces of the puzzle is fruitless.
In the not to distant past I remarked on some rather unusual lab returns for the UOA's for Raven. This happened, if your recall, when a new lot was started on a reformulated batch of Red Line HP Euro 5W40 missed my notice. As such I hadn't a VOA run on the new formulation and picked it up in the Ca/Mg loading of returning UOA's.
Full disclosure. I panicked. Reacted, got upset and then and only then had a VOA run on the new lot. OMG what an idiot I can be. Got it back today and I've corrected the results. Last two entries corrected down and now meeting trend.
There is an improvement to be gained between *W20 and *W30 but nothing gained in iron going higher.
Aluminum
There is little difference between *W20 and *W30 in abating piston wear BUT....
*W40 is a deal maker
Aluminum is huge because rings are supported by pistons and piston wear integral with late stage ring wear. Longer the piston lives the longer the rings live. All rotating parts, cams, rollers, mains and rods are impacted by viscosity more than the add package. Naturally low aluminum wear has an input to total wear but the heavier viscosity also reduces bearing wear. Yes I said the same thing twice differently.
But the thing of greater importance is getting that background VOA. Can you live without it? Sure. Just makes the data noise unbearable for a numbers geek like me. I'd say this motor is off to a fine start. Now, all I have left is finding the basement on TAN/TBN. (OCI)