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Guest Message by DevFuse

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34 replies to this topic


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Posted 17 December 2002 - 09:41 AM

Here is a site that exposes oil filters - the tests were for motorcycle filters, but
my suspicion is that the results would also apply for auto filters.
My own preference is for the Wix.

Happy Holidays -


#2 Guest_synapse79_*

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Posted 17 December 2002 - 09:50 AM

In another thread i was just reccomending fram filters.
I wonder if their new filter with the wire mesh to support the pleats is constructed the same way. It seems unlikely and that test was conducted in 99, i would like to think they have improved since then.

The wire supported pleats I was told make the filter perform similar to a K&N air filter. This filter is also larger to hold more oil, but only marginally. I also like it cuz its rubber coated and doesnt crush in your hand. Next time i have a chance i'll cut one open to see if it has the cardboard endcaps.


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Posted 17 December 2002 - 09:59 AM

Sorry folks - I should have looked a little deeper.
Here is a link for the Automotive Filter analysys :
This is much more specific, for our needs.
Go to " Oil Filter Overview" at the end of the page for
the reviewers summation.


#4 Guest_synapse79_*

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Posted 17 December 2002 - 10:35 AM

I didnt have time to really read over things much, but i still didnt see the new fram filter with the supported pleats. I

noticed on some filters that there is rubberband around the filter element. Why in the world would they do that. What if it breaks? I dont think a piece of rubber floating around the motor would do too much damange, but it sure isnt good.

Was the rubberband there just to hold the filter together for the picture, or do they really put a rubberband in the oil filter?

#5 Guest_synapse79_*

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Posted 17 December 2002 - 10:42 AM

I was just trying to remember which way oil flows through the filter, and its from the outside in, correct? So i guess it wouldn't really matter if it broke.

I guess im going to have to conduct my own study on the new fram filter...

#6 Guest_meep424_*

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Posted 17 December 2002 - 06:59 PM

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#7 Guest_meep424_*

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Posted 17 December 2002 - 07:04 PM

I used frams for years based ona late '80's study showing them as one of the highest filtrattion rates.


I switched. Times have changed... poor/inconsistent quality seems common. Cig butts, missing glue, and most notably a short lifespan on the anti drain back valve. I consistently cured tappity-tappity starts by replacing the fram early. Now I use proline (rebadged purolator) with no complaints.


ps... flow is out-to-in

#8 Guest_HCoble_*

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Posted 18 December 2002 - 07:40 AM

I am curious if anyone has thought about using the H-6 filter on the H-4 engines. The dimensions and threads are supposed to be identical to the H-4 Subaru filters and the bypass valve pressure is the same at 23 psi. The H-6 is supposed to have 201 square inches of filtration compared to 141 for the H-4.

#9 Guest_gotsubarus_*

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Posted 18 December 2002 - 10:16 AM

I have had very good luck with the Purolater filters, and the Napa gold, also the Care quest.

But i will not use the Frame oil filters because they are to tight a filter and clog easier especialy on a used car that you dont know much about.

I dont think that you would need more filtration, if you think your engine is dirty, than change the filter more often. they are easy to get to and inexpensive.

#10 Guest_synapse79_*

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Posted 18 December 2002 - 10:23 AM

This is pulled from the second article, its about Pure One filters.

"After seeing one of these filters cut open, I am apprehensive about this filter. It seems to have so many pleats that it is almost a solid chunk of filter element. It seems like it would end up restricting the flow, more than anything. Purolator has plenty of data on the filtration abilities of this filter and I don't doubt it, but they have no flow data."

#11 Guest_Commuter_*

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Posted 18 December 2002 - 01:11 PM

This study has been around for a while. Last time I looked, it didn't appear to have anything new or to be updated. I'm not sure of the exact date, but it's probably 2 or 3 years old now. Still good info, but becoming dated. (Perhaps someone could research into the timeframe of the study.)

I think the individual did a very good job, but the one big thing missing in many cases is actual filter media capability. By this, I mean the single and multi-pass efficiencies <strong>at specific micron sizes</strong> Personally, I have found very few companies make this info available. If they do, it's usually the high priced performance filters (since they have something to brag about).

I commented once before a long time ago about the person's reaction to the "tight pleats" of the Purolator. Personally, I don't think one can tell anything from the <strong>looks</strong> of the filter media. Yes, you can see if the pleats are evenly spaced, or crooked, or furry or torn etc. But you can't "see" the media at the microscopic level and that is what matters for filtering. What looks like a "solid chunk of filter element" is probably wide open space to an oil molecule. I cut open a Purolator PureONE just this past summer and while it had more pleats than the typical filter, I did not find it "packed". There was still space between the pleats.

One of the other important specs is flow vs pressure drop (or vice versa). It's easy to make a filter with great filtering capability, but it may be so restrictive that there will be a high pressure drop. Again, "looking" at the media gives you no indication of this characteristic. The filter I use employs microglass fibers. It filters to much smaller particle sizes than most filters, however, it has a lower pressure drop per given flow rate than most filters. The two are not necessarily mutually exclusive.

I'm curious as to the information on the greater surface area of the H6 filter. I thought that they were the same as the H4 filters with one minor exception. The H4's need a filter which has a convex (dished out) backplate since they use such a short threaded stud on the engine. The H6 can use a filter with a more conventional concave (dished in) backplate. If you try to use a filter like this on the H4 engine, you may not get enough thread engagement. (I know, I've been there.) This is the only real difference between the Purolator 14459 and 14460. The "60" is specific to Subaru and has the convex backplate.

So there are some more "oil filter" ramblings for you. :cool:


#12 Guest_synapse79_*

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Posted 18 December 2002 - 03:24 PM

that is the idea behind the new fram filter, is to increase flow

#13 Guest_HCoble_*

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Posted 18 December 2002 - 05:44 PM

I should have listed my source for this information. I got the figures of 201 inches for the H6 filter and 141 inches for the H4 filter from the Fall 2002 Issue #20 of The End Wrench. The End Wrench is a publication of Subaru of America.

They listed the part number for H4 as 15208AA060 and the part number for H6 as SOA5165109. I looked up both numbers in a parts catalog I have and the H4 is listed as filter for all models whereas the H6 filter was listed as a filter for the SVX. I think my catalog is only up to 1999 parts which would not cover the newer H6 engines so I am assuming that this filter must fit both SVX and the newer H6 engines(big assumption) The article says "both filters have the same physical dimensions as far threads, O-ring, and bypass valve opening pressure(23 p.s.i.)" but that the H4 filter should not be used on the H6 engine because it would become contaminated faster and allow the bypass valve to open.

It would seem that a H4 filter can at least be screwed onto a H6 engine and be useable, I don't know about the convex shapes of the filter but it would be interesting to know if H6 filter could fit a H4 engine. Maybe someone who owns a SVX , Bean, or VDC could shed some light on this matter.

#14 Guest_Commuter_*

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Posted 18 December 2002 - 09:11 PM

Since Purolator makes the OEM filter for Subaru, it's the same story. There are tiny differences. For example, the Subaru OEM filter does not have an anti-drain back valve. The Purolator filter (14459) does since it fits more than just Subaru. And Subaru must have spec'd a round gasket since that's what they have but the "general purpose" 14459 has a gasket with a square cross section.

Either one will "fit". The threads are the right size and the gasket is the right diameter. It is simple a question as to whether you will have enough thread engagement with the 14459 (or equivalent H6) filter. You may, you may not. Others have reported the same with other aftermarket filters such as Bosch, etc. Most have no problem, some, like me, have had a problem. The H4 engines simply have a very short stud in the block. From what I was able to find out, it may even be a hint under spec. I know that there is a slight difference between my old engine and my new engine. I was determined to use a particular aftermarket filter so I had to come up with a solution. That solution turned out to be an Aluminum washer (for Honda transmission plug) put under the filter stud in order to bring it out a bit. Worked like a charm. (However, if anyone else decides to do this, do so at your own peril.)

Btw, the new H6 3.0L engine does spec the same filter as the SVX. A friend of mine has the Outback VDC and the 14459 Purolator filter is spec'd for it.


#15 Guest_HCoble_*

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Posted 18 December 2002 - 09:55 PM

O.K. I understand now. H-6 filters and equivalents may fit depending on the stud. I think I may have already run into situation before. I have 2 Subaru cars, a 2002 OBS and a 1995 Legacy. I always have the oil change and maintainence on the OBS done at the dealer as cheap insurance to avoid any warranty hassles with SOA. I try to do as much of the work on the 1995 to save on labor (plus I think I do a better job most of time anyway) I usually buy the Subaru filters for the Legacy when I am servicing the OBS (I use the MNBA coupons and use the remaining balance to buy filters) If I am out of OEM filters I usually buy Purolators because I know they manufactor the OEM filters but one time I needed to do an oil change and the parts store did not have Purolators in stock and I bought the store brand from the chart but it would not thread onto the stud and I had to return it for an exchange.

#16 Guest_Legacy777_*

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Posted 19 December 2002 - 08:54 AM


What filter brand/model are you using?

#17 Guest_tom2turbo2_*

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Posted 19 December 2002 - 03:46 PM

That site is very good. www.minimopar.net/oilfilterstudy.html

BTW, I had an XT-6 blown up by the Fram oil filter medium collapsing, no more Fram for me, ever.

The Purolator high priced job is less than Subaru factory pricing with a discount, but either works for me.


#18 Guest_Commuter_*

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Posted 19 December 2002 - 10:14 PM

The oil filter that I'm using is (rather was) made by Dana for ACDelco. It is an Ultraguard Gold filter. My understanding is that it is no longer made. This is an expensive filter: $20 to $30 US, something like that. I got mine through the SynLube company.

In brief:
- heavy construction, high burst strength
- microglass media that filters down to 10 microns and less
- very high single and multi-pass efficiencies
- excellent flow for a given pressure drop
- high dirt load capacity
- wire backing of the pleats
- anti-drain back valve
- by pass valve
- metal end caps
- round cross section gasket, fully captured

I've cut a used one open. There is not an excess of pleats. The filter probably has only average filter surface area. The microglass fibers however are much smaller than cellulose fibers. They trap smaller particles while still allowing good flow (since the fibers themselves don't take up as much space).

I have a couple on hand, but I don't know what I'll be turning to next. I'm waiting to see what SynLube can source. I trust their judgement.


#19 Guest_synapse79_*

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Posted 20 December 2002 - 02:05 AM

what do you guys think about running a filter relocator with like a 1qt. filter?

#20 Guest_Legacy777_*

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Posted 20 December 2002 - 08:20 AM

You mean like one of those additional bypass oil filtration kits. I heard they work pretty good. You need to use them in conjunction with the standard filter, because they can't flow the amount of oil needed for normal operation.

If you were to do this, I'd almost highly recommend going to synthetic because it's not really worth doin the kit unless you extend your oil change interval. The additives in dino oil are goin to get used up a lot quicker then synthetic.

I for one can't leave oil in a car for too long.....call it a sickness....or whatever.....I just can't. So one of these kits for myself prob wouldn't be the best investment.

#21 Guest_synapse79_*

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Posted 20 December 2002 - 11:13 AM

I think its too late to switch my impreza to synthetic. It has just over 70k on it and its not worth the risk of wrecking the oil rings. I just change my oil every 3000 miles, whether its synthetic or dino oil.

I dont think we are thinking of the same filter setup. The serious honda guys around here do it(not the ones that put stickers all over). They get some part that goes where the oil filter would go, that just has an inlet and outlet. then those go to another base where a huge filter mounts. They like it cuz it provides the system with more oil and acts like an oil cooler somewhat. Half of them are running around with motors that cost 3times what the rest of the car costs... One of them that owns a garages that im good friends with drives from michigan to vegas every other month over the summer to pick up motors imported from japan.

#22 Guest_Frag_*

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Posted 20 December 2002 - 01:26 PM

Synapse, I've switched to Mobil 1 synthetic when my 2.2 had 140,000 kilometers and after two ful years and now 180,000 kilometers,everything works fine and no leaks that I know of.

#23 Guest_synapse79_*

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Posted 20 December 2002 - 07:46 PM

you got lucky, or maybe I waws just unlucky

In one my integras i switched it to synthetic with about 70kmiles and a month later it would loose about a half quart of oil out the exhaust about once a week.

#24 Guest_spagemurray_*

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Posted 20 December 2002 - 10:31 PM

Please explain this ludicrous statement. It's for sure you know very little about engines let alone oil. You need to spend some serious time on www.bobistheoilguy.com particularly the forum before making statements like that.

#25 Guest_trinket_*

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Posted 20 December 2002 - 11:20 PM

I switched my '95 Legacy to synthetic and put the bypass filter on when I bought the car with 70,000 miles on. It's now at 190,000, with no apparent problems, so you should be fine changing to synthetic if you want. I use Mobil 1 10-30, letting the oil go for 20,000 miles, changing the full flow filter every 10,000 miles and the bypass filter at the 20,000 oil change. Everyone has a different twist to the story, so here's mine.

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