Do oil filters matter?

That depends on who you talk to...or what you read.
The late, great Bob Winters of Bobistheoilguy.com fame ran his car with the oil filter completely bypassed to see if it would make a difference on used oil laboratory analysis results. Apparently there was no conclusive evidence that the filter made any difference in the oil contamination levels that the laboratory analysis could detect. 

...In my opinion, since there seems to be a limit in particle size that oil analysis labs can detect, this does not necessarily mean there were no filterable abrasive particles in the oil anyway.

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Remember the original Volkswagen Beetle?
These engines originally used no filters at all and they seemed to reach 100,000 miles at least as often as other cars' engines that had filters.

...To be fair, the strategy for a well maintained, long lived old VW engine was to change the oil about twice as often as filtered engines required it. This would certainly get rid of most of the build up of abrasive particles and sludge in the VW engine.
                                     
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Ford Motor Company experimented with some of the first full flow oil filters (the modern method where all oil must pass through the filter on the way to the engine internals) back in the 1950s and found an approximate halving of abrasive engine wear...And this with the likely primitive filter media available at the time.

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Other credible sources say that the filter you choose is more important to engine longevity than the oil you use.

...But then again, look how cars so often go 200,000 or even 300,000 miles nowadays with little owner thought or knowlege about filters or oil. They just use whatever the shop or oil change place uses.

 
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Bottom line for me? Having seen the junk stuck to used filter elements that have been opened, I don't want that stuff flowing around in my engine between oil changes.

Next: Flow vs Filtration