How many miles can you go on an oil filter?

[stranger706]

I've been wondering about this for the past week. I recently changed the oil in my Mom's new 2010 Honda Civic while she was visiting us. The oil had 7000 miles on it and the OLM was at 20%. By my estimate she could have gone almost 9000 miles on this oil, going by the OLM. Her commute is mostly hwy. But since she was here I went ahead and changed it per her request.
I was reading with interest the OCI in the owners manual. It states that the oil filter should be changed every other oil change.

In other words, if she had gone the full OCI according to the OLM, which would have been roughly 9000 miles, then the filter should be changed roughly every 18,000 miles if you go by the Honda owners manual.

Can regular oil filters really go that far? I really would have no problem following that schedule. I know that a lot of people are still conservative about this sort of thing and would change it anyway.

I guess my main question is this:

Is there any proof that a regular oil filter will not go 18,000 miles? Or are people just basing their opinions on old fashion traditions and myths?

 

[Mr Nice]

20K miles

 

[ZeeOSix]

"How many miles can you go on an oil filter?"

The answer to the question depends on MANY factors.

 

[Quattro Pete]

Originally Posted By: stranger706


Is there any proof that a regular oil filter will not go 18,000 miles?

Actually, just the opposite. Many cars in Europe run such long intervals (30k km, or 2 years), and as far as I know, they're still doing fine.

The paper filter in my 530i is expected to make it through about 15K miles. Same with the MB, although the MB filter is made of fleece, not paper.

 

[bullwinkle]

In an ULEV like the Civic that is new (or well maintained) the oil doesn't seem t get very dirty. My wife's xB's oil doesn't even look dirty after 5K (factory recommended OCI).

 

[pidster]

It depends. On a modern Honda with no issues, a good quality filter (OEM or better) will handle that with ease. Some motors will plug one up in half that or less.

 

[tig1]

I never reuse a filter. I wouldn't put 4 qts of new oil with 1/2-3/4 qts of old oil.

 

[JOD]

Originally Posted By: tig1
I never reuse a filter. I wouldn't put 4 qts of new oil with 1/2-3/4 qts of old oil.


That's certainly fine, it's your decision. But it's an emotional one, not a rational one.

A Honda oil filter holds about 6-8 oz. of oil. Many engines hold close to that as well, so you're already likely mixing "old oil" with new oil. Balance that with the fact that the older filter offers better filtration, and you're left with the question of what's worse for the engine; the insolubles from the left-over oil, or the decreased filtration?

Every UOA I've seen were people have run a filter for 2 changes have shown better numbers on the second change.

Me, I'll reuse the filter, unless it's a very high-efficiency filter to begin with, in which case I'd be a little concerned about hitting the filter's capacity.

 

[ZeeOSix]

Originally Posted By: JOD

Me, I'll reuse the filter, unless it's a very high-efficiency filter to begin with, in which case I'd be a little concerned about hitting the filter's capacity.


Or hitting the filter's bypass setting, which would then send unfiltered oil down your engine.

There is really no real sure way to tell when the filter is going into bypass mode unless you had some gauges on both sides of it, and no car I know has that kind of instrumentation setup form the factory.

 

[silverrat]

Audi OEM spin on filters state 30,000km / 2 years right on the can.

 

[JOD]

Originally Posted By: ZeeOSix


There is really no real sure way to tell when the filter is going into bypass mode unless you had some gauges on both sides of it, and no car I know has that kind of instrumentation setup form the factory.


Well, I'd disagree with that, sort of...

You can tell post hoc how the filter is coping with a certain OCI, simply but cutting it open and visually inspecting it or by looking at the insolubles in a UOA. Either (or both) of those things should make it pretty clear if the filter has reached bypass mode.

While this will be specific to one's vehicle, driving habits and filter, it should on a case-by-case basis help one figure out how long he/she can run an oil filter. Obviously it doesn't tell you what's going on while it's in there, but if you have concerns you can start stretching out the interval for the filter gradually, inspect the filter, and go from there.

That said, I find it pretty unlikely that Honda would be recommending up to a 20K interval on an oil filter if they felt it were problematic.

 

[Soobs]

If your vehicle manufacturer recommends changing it every other oil change you'll be fine so long as you're using an OEM filter. Anything else and you're just running an experiment irregardless of any wild aftermarket marketing claim.

In any event. I think we should ask Mr. Owl.
http://www.youtube.com/watch?v=LZ0epRjfGLw

 

[ZeeOSix]

Originally Posted By: JOD
Originally Posted By: ZeeOSix


There is really no real sure way to tell when the filter is going into bypass mode unless you had some gauges on both sides of it, and no car I know has that kind of instrumentation setup form the factory.


Well, I'd disagree with that, sort of...

You can tell post hoc how the filter is coping with a certain OCI, simply but cutting it open and visually inspecting it or by looking at the insolubles in a UOA. Either (or both) of those things should make it pretty clear if the filter has reached bypass mode.


There is no sure way you can look at a cut open filter and say it has been going into bypass mode while in use, regardless of how much debris is found in the media.

Now if you were a filter maker or a car manufacture that had an oil filter test lab and some sophisticated test equipment you could run filters and load them up until the bypass valve states to open to determine their debris holding capacity and expected OCI in real use.


Originally Posted By: JOD
That said, I find it pretty unlikely that Honda would be recommending up to a 20K interval on an oil filter if they felt it were problematic.


True ... and I'm sure Honda has done some of the testing I speak of to determine that OCI, but of course this in on their OEM filter only. It is also probably stipulated from Honda that OCI is for non-severe service so it's kind of up to the owner to determine his driving habits and if it falls in to the right OCI recommendation from the manufacture.

For non OEM filters, all you can do is go by the filter manufacture's OCI recommendation to be safe.

 

[BLKTIGR55]

Stay away from dirt roads if you plan on re-using the filter.

 

[slalom44]

My last OCI was over 35,000 miles without changing the filter. The previous two OCIs were over 30,000 miles. The media still looks great, and my UOA is great. Admittedly I also use a bypass filter but I really don't think that makes much of a difference.

I have used a Trasko filter on my Highlander many times for 10,000 mile OCIs. That has a wire mesh full-flow media, and when I clean it out, there is hardly anything in it.

IMO unless there is something wrong with your engine, a decent brand filter should last well over 20,000 miles.

 

[HTSS_TR]

Originally Posted By: slalom44

IMO unless there is something wrong with your engine, a decent brand filter should last well over 20,000 miles.

I agree. Honda must done their homework before they recommend changing oil filter only on second oil change, and the oil change interval can be as long as 10k miles or more.

I examined the cartridge filters of my E430 after 12-13k miles and didn't much anything on the filter, it looked like it could be in service for another 12-13k miles. But I changed it anyway because I bought a bunch of filter on sale some years ago. Next time I will try to reuse the filter and inspect it every 2-3 month to see if it can survive the 2 oil changes of a total of about 24-26k miles.

 

[Spyder7]

I reuse filters sometimes. It depends on how many miles I expect to get out of the oil versus how many I decide to use the filter for. This filter is already on its second OCI. It could go a 3rd, but the next OC and the filter mileage are close enough that I`ll do both next time instead of the oil and filter shortly after (sacrificing a few miles for convenience).

I go more by convenience and getting a reasonable interval from a quality filter, than trying to perfectly match the oil OCI to a filter and doing them both every time. Its not necessary. It may be comforting from a psychological POV, and if that's the case, no harm in doing it; but objectively, if the filter has lots more life than the oil, it doesn't need to be changed just because the oil does.

The 2 or 3 ounces of used oil remaining in the filter will have no more impact than the couple ounces still stuck in the sump; not when 4+ quarts of new oil are going in. Any impact is negligible and easily dismissed.

-Spyder

 

[yaris0128]

I dont care how many miles are on my filter. New oil gets a new filter. Its not worth saving a few bucks, and only a FEW bucks.

 

[Malo83]

Originally Posted By: yaris0128
I dont care how many miles are on my filter. New oil gets a new filter. Its not worth saving a few bucks, and only a FEW bucks.

Thank You yaris.

 

[Spyder7]

Originally Posted By: yaris0128
I dont care how many miles are on my filter. New oil gets a new filter. Its not worth saving a few bucks, and only a FEW bucks.


That's purely a matter of opinion, and its something entirely subjective. Nothing wrong with doing that as that's the way its been done for most of history. New technology and research suggests that its no more necessary than the 3k or 3 month OCI, but many stick to that still too.

Whatever works for you.

-Spyder