Originally Posted By: kschachn
I'm not disagreeing with you. It's also true that the lower efficiency filters will catch the same particles but it will take longer to do so. The same grit is going to be removed regardless.
And conversely just because a filter has higher efficiency doesn't mean it will trap a particle on the first pass either, unless it is 100% efficient.
I think it is easy to publish efficiency ratings (and make like it is a huge deal), but not explain if it is significant. Once again, in the end a low efficiency filter will trap the same particles as a high efficiency one will. Nobody talks about the effect of retention time of a particle in suspension, that is the root of determining the relevance of efficiency ratings.
Originally Posted By: FetchFar
Originally Posted By: kschachn
I don't know either. I just keep seeing that little Amsoil chart, and while the numbers being presented may be accurate no supporting data for why it is good or bad is ever given.
Going by observation, most people will agree that the more grit you get out of the oil, the better the wear performance. A few engineering studies have been done:
http://www.amsoil.com/techservicesbullet...gine%20wear.pdf
and microgreenfilter.com also builds a case for tighter filtration and sells to fleets as cost-saving strategies.
The SAE study cited in the Amsoil PDF web page is a famous one for justifying better filters. Also, remember the ISO 4548-12 test procedure is a multi-pass filter efficiency test that does try to duplicate the actual continual-flow performance of filters in engines. Very simply, the cheaper oil filters have more bigger holes, where the more expensive glass-blends or all-glass have smaller holes, naturally trapping more smaller particles.
There may be a point to be made about oil filters: Similar to air filters, particles trapped get smaller and smaller as the oil filter ages, up to clogging of course. I like the better oil filters (like Fram ToughGuard or Ultra) because you get great filtration from the start, when new, and their dirt-holding capacity is higher than the cheap cellulose filters.
Seems the only advantage of cheap cellulose-only media oil filter is helping the maker's profit margin. Thats where the consumer's interest is different than a filter company's goals. We think a couple of extra bucks for better filter performance is not much extra cost, while the makers are selling their filters to uninformed citizens and quantity-quick-lube shops trying to pinch pennies.
