Is there a larger oil filter available for the Outback

[Petersubaru]

just wondering if some one is useing a larger oil filter then the stock one available for a 2001 outback 2.5L...I was surprised to see that the filter is even smaller then what is for the older EA82 models...I get the impression that filtering the oil in more modern cars is not that important anymore

[Snowman]

The filter in the WIX catalog is the same one that Subaru used to use on all the EJ cars, which is still smaller than the EA filter, but it's way better than the new factory ones, which are microscopic.

 

Just curious, has anyone tried just putting an EA-series filter on?

[Petersubaru]

I reason I orginally asked the question is that I assumed that the EA series oil filter would fit..but no way...the threaded fastening hole is to small...I found this out in the middle of an oil change and far from the store...once at the store I could not find in there limited selection a larger filter with the slightly larger opening...

The filter in the WIX catalog is the same one that Subaru used to use on all the EJ cars, which is still smaller than the EA filter, but it's way better than the new factory ones, which are microscopic.

 

Just curious, has anyone tried just putting an EA-series filter on?

[Manarius]

Filter size is irrelevant. It's what's inside the filter that counts.

[svxpert]

<<Filter size is irrelevant. It's what's inside the filter that counts.>>

totally agree, filter quality is much more important than the size of the outside case.

[porcupine73]

True, you need a good efficient filter media and a bypass that is well made and doesn't open prematurely. I've been using amsoil eao36 (crosses to Wix 51347) which is a bit longer than stock but it's not as big around and actually when calculating the volume they're about the same. In the 20mmx1.5mm thread size there's not a lot of large filters.

 

Here's the two Wix equivalents I've tried: Thread Size: 20X1.5 MM

Wix# height diameter bypass

51334 3.194" 3.252" 8-11psid

51347 4.828" 2.921" 8-11psid

 

If you really want a bigger filter, I saw on another board about a guy who unscrewed the factory Subaru nipple for the filter and put in one from a Ford. This gives you like a 3/4" thread size (very common and there's tons of filters with this thread) so he got some filter like 6" long, the only size restriction being keeping the filter diameter small enough to keep from rubbing on the timing cover. I can see if I can find the thread again if you're interested.

[Petersubaru]

I certainly agree Quality is #1..I am just seeking to understand why the newer subarus have smaller filters then the older ones, (both being an OE product), while at the same time the oil change intervals have increased for the newer models when all subarus are running cleaner then ever??...one very small filter fits all ,2.5l or 3L ???? ... I fail to understand how going smaller can be an improvement...I asked these same question to the tech guy at the subaru dealer where I just purchased a 2001 outback, since they would like me to come in for there factory recommended oil changes at 4000mi or less...I asked them, WHY,..their simple response is: "that the car will last longer"...A little hard to believe since I have 2/ 1986 loyales with 250,000 miles on each them with excellent compression and have gone with far longer oil change intervals then 4000mi...but then again I have always used the larger filter (OE diesel filters from VW)...

<<Filter size is irrelevant. It's what's inside the filter that counts.>>

 

totally agree, filter quality is much more important than the size of the outside case.

[Petersubaru]

Porcupine; if you can find the thread again , I would very much appreciate it.. thankyou

True, you need a good efficient filter media and a bypass that is well made and doesn't open prematurely. I've been using amsoil eao36 (crosses to Wix 51347) which is a bit longer than stock but it's not as big around and actually when calculating the volume they're about the same. In the 20mmx1.5mm thread size there's not a lot of large filters.

 

Here's the two Wix equivalents I've tried: Thread Size: 20X1.5 MM

Wix# height diameter bypass

51334 3.194" 3.252" 8-11psid

51347 4.828" 2.921" 8-11psid

 

If you really want a bigger filter, I saw on another board about a guy who unscrewed the factory Subaru nipple for the filter and put in one from a Ford. This gives you like a 3/4" thread size (very common and there's tons of filters with this thread) so he got some filter like 6" long, the only size restriction being keeping the filter diameter small enough to keep from rubbing on the timing cover. I can see if I can find the thread again if you're interested.

[porcupine73]

OK, well I'm having trouble finding the thread because this other board switched ubb versions so the old link I have doesn't work, but basically this guy says he "found a slick Mopar part that has M20x1.5 threads on one end and 3/4x16 on the other. It also has a little (about an inch) 'appendix' that I had to cut off, but I've been using it on my Subaru ever since."

 

So you basically unbolt the existing filter nipple and put this modified nipple in place, and presto you can run 3/4" thread oil filters. Then you could maybe go with something like the 7" long Wix 51773 (but it's micron rating isn't super good):

Height: 6.982"

Diameter: 3.663"

[subeman90]

IIRC the H6 filter for the 3.0 engine is longer

[Petersubaru]

Thanks, I will look into it...also, would you know the micron rating of the smaller subaru filters..with the tight tolerances of the subaru bearings, a smaller micron filter would be very important...then certainly the size of the filter would mean nothing here if the micron rating is poor (larger particles)....

OK, well I'm having trouble finding the thread because this other board switched ubb versions so the old link I have doesn't work, but basically this guy says he "found a slick Mopar part that has M20x1.5 threads on one end and 3/4x16 on the other. It also has a little (about an inch) 'appendix' that I had to cut off, but I've been using it on my Subaru ever since."

 

So you basically unbolt the existing filter nipple and put this modified nipple in place, and presto you can run 3/4" thread oil filters. Then you could maybe go with something like the 7" long Wix 51773 (but it's micron rating isn't super good):

Height: 6.982"

Diameter: 3.663"

[porcupine73]

The typical 'nominal' micron rating is like 19 or 20. There's a whole system for testing micron ratings, like single pass efficiency, etc., I think nominal efficiency is it will catch at least 50% of particles that size and larger on the first pass but I can't remember. And there's the beta numbers.

 

Anyway, it's always a tradeoff in the media between how small a particle it can filter and still have not too much pressure drop. If you want really small filtration, like 1 micron or even submicron, then you need to install a bypass filter in addition.

[Petersubaru]

I don't know about the by-pass system as to be any better or even as an improvement...in an age when we need to be consuming less thru better efficientcy, I can only think about the canister type filters such as Freightliner(chysler)or VW, were by their diesels are running 10,000 miles between oil changes because these filters are taking out anything larger then 10 microns...they have literally extended the oil change intervals by 4 times since the mid eighties ...what has subaru done?.. they (subaru) have asked us to increase them ??? I can only ask, are these motors not as good as they were in the past?

The typical 'nominal' micron rating is like 19 or 20. There's a whole system for testing micron ratings, like single pass efficiency, etc., I think nominal efficiency is it will catch at least 50% of particles that size and larger on the first pass but I can't remember. And there's the beta numbers.

 

Anyway, it's always a tradeoff in the media between how small a particle it can filter and still have not too much pressure drop. If you want really small filtration, like 1 micron or even submicron, then you need to install a bypass filter in addition.

[porcupine73]

Yes, it is more and more about efficiency and reduced costs isn't it. There aren't really many passenger vehicles that suggest extended oil change intervals esp. for 'severe service' operating conditions. The 'oil change monitors' are a somewhat recent thing I guess.

 

Well there are a few factors involved there with diesels. HDD oils have a higher TBN (i.e. 12+) vs. gasoline engine oils which have maybe 8 if they're good, so the diesel oil can neutralize acidic by-products longer. Also, those diesels have much larger sump capacities than any passenger car. And those diesels don't make a lot of short trips so condensation and fuel dilution is less of a factor. With a good bypass filter and a good HDD oil in the engine the Subaru could easily run that oil 18,000 miles or more and get a good used oil analysis. Diesel oils also have more AW additives than PMCO.