It's not sludge, again, you clearly don't know what sludge is, I provided an excerpt from a tribology document that clearly outlines what sludge is. Sludge requires a moisture component.
Yes, it had a ton of dark varnish. The Expedition, which yielded the same stuff, was not ugly, and only had some very light varnish, zero sludge.
The BMW was heavily varnished, as I noted. Please, read through the flow chart to properly understand the various types of deposits, you are using "sludge" rather broadly here, when it has a very specific meaning.
There's nothing being congealed, you are seeing the results of material being removed/picked-up, which is then held in suspension by the detergent/dispersant package, which ensures that it gets to the filter. That's the purpose of the DI package, to prevent agglomeration and to get contaminants to the filter, where they can be filtered out.
I've asked Dave
@High Performance Lubricants about this, and yes, it's expected behaviour for the first few OCI's. Where do you think the stuff that's cleaned-up ends up if not in the filter?
No, that's carbon, in oil.
Again, you clearly don't know what sludge is. I highly encourage you to process and understand that flow-chart.
You are also implying, in maintaining that everything is sludge, that M1 EP 0W-20, run at reasonable intervals, "sludged" my RAM 1500 engine in 55,000km. How likely do you think that is?
Yes, Mobil 1 0W-40 was actually advertised as cleaning an engine, not just removing sludge, but actually cleaning up varnish and other deposits.
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That's sludge, not varnish. Sludge, which is soft and not bonded to surfaces like laquer or varnish, is very easy to remove. You don't need AN's or esters to remove it.
The verbiage for the 0W-40 is as follows, note the lack of word sludge, they explicitly note it just has the ability to clean. This differs considerably from the language used for the EP products, and mirrors my experience with the two families of products.
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