Re: Schaffer oil?
I have only seen the effects of this oil in OTR diesel engines when I was working as a diesel tech. We had a customer that would buy this brand of oil by the barrel for his whole fleet of trucks. He swore by this stuff. We advised him to stay away from this oil. His engines were always in the worst shape compared to other in-frames with similar mileage.
We would always see the main and rod bearings badly worn. The inside of the engine was always dirty, no sludge but the oil and the engine interior was very black. Not even Detroit Diesels where this dirty. We are not sure if he was just putting more miles on his oil before oil changes.
So this is my only experience with this oil. I myself would not try it. If you can, cut the oil filter after the schaefer and please share. Good luck!