It seems like a million times the "dirty underwear analogy" has came up whenever discussing using a quality filter for a 2nd interval. Yes I know those who use it think its cute and they feel real clever, but honestly its flat out wrong.
Keeping a filter on after 5,000 miles is not like 'reusing dirty underwear'. Question, on a normal day, how many average people stop in their tracks at 12 noon to rush home to change their underwear out? Why not? Beacuse your underwear at noon is not "dirty, full, or used up" in normal circumstances. If you insist on this analogy, you could change your underwear at 12 noon, but why? In most cases nothing would likely be gained by doing so. Very likely its OK until the end of the day.
This is what goes on with most filters. They are tossed at 5K or so, with another unused 5K capacity wasted. Of course there are exceptions, but those are pretty rare. Look at all the C&P filters posted here. Honda certainly believes in 2X intervals. Notice if Honda says "use a 0-20 or a 0-16 oil" no one dare questions it? But Honda says 2X filter intervals and people scoff.
I get it. For many years I did not want to believe a 2X interval was smart, but I do now. Too many great examples in C&P, and previously owning a Honda, and understanding that significant oil is left in the engine regardless of the filter interval has convinced me. Now going on 10 years of 2X filter intervals and zero issues. All to their own though. Changing a filter every time will not hurt a thing, other than your additional costs. But please, lets leave the "dirty underwear analogy" where it belongs, in the dirty clothes bin. Its just wrong.
Keeping a filter on after 5,000 miles is not like 'reusing dirty underwear'. Question, on a normal day, how many average people stop in their tracks at 12 noon to rush home to change their underwear out? Why not? Beacuse your underwear at noon is not "dirty, full, or used up" in normal circumstances. If you insist on this analogy, you could change your underwear at 12 noon, but why? In most cases nothing would likely be gained by doing so. Very likely its OK until the end of the day.
This is what goes on with most filters. They are tossed at 5K or so, with another unused 5K capacity wasted. Of course there are exceptions, but those are pretty rare. Look at all the C&P filters posted here. Honda certainly believes in 2X intervals. Notice if Honda says "use a 0-20 or a 0-16 oil" no one dare questions it? But Honda says 2X filter intervals and people scoff.
I get it. For many years I did not want to believe a 2X interval was smart, but I do now. Too many great examples in C&P, and previously owning a Honda, and understanding that significant oil is left in the engine regardless of the filter interval has convinced me. Now going on 10 years of 2X filter intervals and zero issues. All to their own though. Changing a filter every time will not hurt a thing, other than your additional costs. But please, lets leave the "dirty underwear analogy" where it belongs, in the dirty clothes bin. Its just wrong.
