[screamingchief]

Originally Posted by 69birdboy

This leaves me for now with only one question. Assuming this filter change doesn't fix the issue, would a loose clearance want a thick oil (presumably more pressure?), or a thin one (presumably more flow?)? I would think a thicker oil would be appropriate, around 50W or something. What about using a solvent of some sort? Would that just make the problem worse?

Honestly,when working on cars,you really need to get in the habit of assuming nothing.

Wait till you change the filter and see what happens,then figure out the next step.

Typically yes,generally speaking loose clearances = thicker oils and tighter clearances = thinner oils,but that's not necessarily always the case,as there are a whole lotta other dynamics that can come into play as well,such as the oil temp range the engine is operated under,as well as a few other variables,but that said there are plenty of "loose" engines out there that use thinner oils successfully,but those are generally racing engines that get much more frequent oil & filter changes (w/filters being cut open for inspection and such) and engine teardowns & bottom end inspections,so dont expect to use those engines as a guide for what's right for a higher oil change interval that a street car will use.

So long as the oils viscosity & pressure is sufficient to maintain the hydro-dynamic oil wedge in the engine bearings,then the bearing clearances are really more a concern of the engines intended useage,with a racing engine using looser clearances than a high mileage street engine would use.

And I would say no to any solvents in the oil/crankcase,IMO the only thing that's really truly meant to go in an engines crankcase is engine oil itself.

And again,worry about any future problems as they arise,not before the fact.

HTH

Bret P.