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Wear metals are low. So I assume this is not a young engine. Total vehicle miles are low. The chrome and nickel are low, thats the piston rings. The iron is low, mostly cylinder walls.
I don't know if fuel is a problem, the rings are obviously seated. Modern low volitility gasolines are just that. The crankcase will drive off the volitile components. Take some gas and put in in a container and leave it outside for a few days where it can't get rain and watch what happens. It will not go away. So perhaps the residual will not effect viscosity as one might expect. In any case the viscosity is in spec so nothing terrible is going on. .5% fuel contamination is .64 ounces, not enough to have any significant issues. A high fuel contamination figure could reveal a defective injector spray pattern that was wetting cylinder walls. That would be bad as the oil film on the cylinder wall would be degraded. One would have high chrome and iron revealing extreme wear and maybe some aluminum as well. So the fuel contamination is something that would alert you to a problem before catistrophic failer or damage occured, and thats really what such tests are for. Another example is high wear metals, high silicon/silica and perhaps sodium. This can occur when there is an induction leak around an air filter perimeter or an open duct. Dust and dirt are getting into the engine. Sodium will be from road salt if the vehicle is being operated in snow with road salt. It is rare that you are going to see a oil analysis that suggests that the oil is defficient. Why, because folks who spend money on such are using high grades of oil. The only time that thing get interesting is when folks are changing the oil once a year or longer. In these cases they are changing filters from time to time which introduces new oil which replentishes the additives. When the diesel heads are doing this, remember that diesels do use engine oil and makeup oil also addes fresh oil and additives. Most of these extended drain freaks are running bypass filters which will remove the small wear metal particles that a full flow filter cannot remove. If you don't have a bypass fitler you must drain to remove the wear metals. A really strong oil sump magnet will remove the iron/steel wear metals from the block, rings, cams, followers, chains, sprockets and oil pump. Even with ED's low iron, if he had one of these he would see magnetic mud on the magnet when changing the oil, not much but it would be there.
So if you are using really good oils and changing often, you will not see degraded oil on an analsys. What you can see are wear metals from something going wrong that have nothing to do with the quality of the oil:
induction leaks letting dirt into the engine
bad injectors wetting cyliner walls (use Techron or others)
coolant in oil from a head gasket leak or a crack or porosity
wear metals from something failing, mehanical or deficient oil pressure
So perhaps the focus on the oil properties for good oils without extended drains is missing the point. Its the wear metal conamination or other contaminants that are the issue and these will not be a factor of what oil is being used.
Almost off topic: high wear metal contents acts like a catalyst and this can cause oils to get thick and gooey. We have see that happen to several NG900's, mostly the 2.3 NA engines. In many cases probably a combo of negect and dyno oil.
posted by 207.43.195...
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