Originally Posted by oledoc2u
Kind of like catsup Dave...if you looked at it thru a microscope, you probably wouldn't eat it....lol Do as you wish...but oil is a refined lubricant...we did this experiment in a shop class in HS 40 yrs ago, and I really don't think much has changed...other than only a handful of refineries are left here in the US...The Good Lord only knows what we are getting from your back yard....
And if you want to use a re-fined oil, it will contain about 70% of good oil mixed back in after the contaminants are removed from the old oil. You only hope they removed all those contaminants with their filtering before adding in the new oil. Again, not worth the risk in my opinion...I will stay with my routine, I haven't had an engine fail yet, and my Cummins is at 540,000 with plenty of miles left. Still doesn't use any oil between the 10,000 mile changes. Lastly, always buy a good oil filter, don't skimp there either... There are vast amounts of lubricants that come from crude, just use quality oil...