The filter makers offer their own limited warranty; what the OEM would not cover, the filter maker will, AS LONG AS you use their recommended filter for the specific application. If you don't the burden of proof shifts upon you; good luck with that in arbitration against their reams of data, mounds of money and team of lawyers.
Regardless if you believe their selection is correct or not, they offer their limited warranty as a means of protection providing you follow their recommendation. They offer NO ASSURANCES if you choose to venture off the reservation.
It would behoove you and others to go read and educate yourselves on the M/M act at the FTC website. Written limited warranties are not for the consumer's protection; they are for the manufacturer's protection! Limited warranties are a means of (as the title suggests) limiting the warranty provisions to stated terms so as to not offer a limitless warranty. Hence, the conditions stated in a limited written warranty can exclude consumer-driven choices to act outside the limitations. This shifts the burden of proof of proper application from the maker to the consumer.
https://www.ftc.gov/tips-advice/business-center/guidance/businesspersons-guide-federal-warranty-law
In short, if you follow their recommendation (even if it's a bad one), they are easily compelled to honor their warranty. If you do not, they have the grounds to outright deny your coverage, or at least force you into a proceeding that will take months, if not years, and cost you tons of time, effort and money. It would likely be cheaper for you to buy a new engine than win the arbitration/case. And because it would be YOU taking THEM to court (arbitration), the burden of proof is upon YOU to prove your selection was not in error; against all their hours of engineering data, experts witnesses, etc. And whom do you have in your corner? A handful of BITOGers who guestimate applications with no data to back it up.
And what's your reward for that risk?
No proven benefit whatsoever.
Here's what irritates me; this is why I'm "wound tight" about this topic ...
We have newbies that come here, and people that lurk, and accept much of this "advice" from BITOGers as sound, sage wisdom. That is a very poor, nearly irresponsible approach for we BITOGers to take.
I have no objection if you run what makes you feel good; nothing wrong with that at all.
But DO NOT offer this as if it were sound, reasoned, proven selection criteria, because it's not.
- There is no proof that slightly upsizing a filter has any true, tangible benefit
- There is every expectation that if you do use a "non-approved" filter, you risk no warranty coverage.
The risk is real and the reward is imagined.
THAT is the message we should be providing people.