Echomirage
I'm Awesome
I just went over the entire thread, and could not see how many miles are on this engine. That would be useful information when diagnosing mechanical condition. You were going to pull the pan anyway, and I think this is something you should do.
Lubrication of bearings is all about oil flow, not pressure. Low pressure just indicates either that the pump is not flowing enough oil, or that the bearing clearances are too big, leading to a lack of resistance to flow.
A clean sump and pickup, clean oil filter, enough oil, and a good gauge. That should be the starting point to determine if there's a problem here. If you get 25 psi at normal rpm hot, I think your engine is ok.
150K, im the 3rd owner. the 2nd owner did very little in terms of maintenance, unless it was broken. he owned it 10 years and only put 20k on it in the 10yrs. im not sure he changed the oil much at all.....the filter was rusted. of course i immediately did the oil and tune up. it was seriously neglected during his ownership. i dont think it was ever washed or vacuumed, let alone had preventive maintenance done. it was running on 7 cylinders, with #8 plug caked up solid.
i dont hear any new or bad noises when running. no ticking, slapping, grinding, etc. i went for a longer drive yesterday, and saw the dash gauge fluctuate again. it did it a little erratically; it wasnt a steady drop. it wavered and shook, so it could be a bad sending unit.
since the oil sat for so long with no use, im thinking sludge in the pan. i also looked up what it takes to pull the pan, and i doubt id be able to do it, especially alone. i dont have a soul to help me here. i may just buy a high pressure pump from rockauto, and bring it to a place and let them mess with it. i might shop around for a better quality gauge also, but even a cheap unit couldnt be that far off of actual pressure.