Oversize oil filter: Subaru Outback 2.5 4th gen

[ZeeOSix]

Originally Posted By: geeman789
Originally Posted By: webfors
Originally Posted By: fdcg27
It also might be a good idea not to increase length, since doing so will expose the filter directly to heat radiated from the exhaust.


I never gave this explanation much concern since, well, it's circulating hot oil. Any heat would be quickly regulated by the flow of oil.

That being said, the 7317 hangs an inch lower than OEM. The paint isn't baking off, the can isn't heat damaged, no sign of any impact from additional heat whatsoever.


The longer filter, at least on my Impreza, still has close to an inch between the filter and the exhaust... unless you sat stationary for an hour, I seriously doubt the filter is any hotter... and that filter location is already HOT, given the exhaust routing...


There is also the heat radiation factor, which occurs even if you're driving 80 MPH down the highway. I'm sure the exhaust system has a heat shield around it, which helps reduce the radiation effect. And if the filter is painted white vs black, then it will absorb much less radiation heat transfer. A chromed filter would absorb basically no radiated heat.

I agree, there probably really isn't much difference in heat pick-up by the oil filter based on it's length ... the color of the filter would have a bigger factor.

 

[FutureDoc]

Keep with Wix/Napa 7055 (wix) or 57055 (napa) filters and you will be golden. Even Microguard might be an option but availability s limited. Some claim the 1334 filters "work" but the bypass is incorrect. Also, pass on Purolators. Tearing is a factor and I know I have had two failures on my older Gen1 OB.


FYI, 2005 is 3rd Gen OBs.

 

[fdcg27]

Sure, but there must be a marginal increase in radiated heat absorbed by the additional area of the can and it can only make the oil warmer.
That might be a good thing or a bad thing, depending upon how hot the typical NA 2.5 gets its oil in normal use.
Might actually be an advantage, but if Subaru thought that, they would have used a longer can.

 

[webfors]

Originally Posted By: fdcg27
Sure, but there must be a marginal increase in radiated heat absorbed by the additional area of the can and it can only make the oil warmer.
That might be a good thing or a bad thing, depending upon how hot the typical NA 2.5 gets its oil in normal use.
Might actually be an advantage, but if Subaru thought that, they would have used a longer can.


True, but if Subaru was all knowing (or all caring) they would have used a closed deck design for the ej25 and spared us all HG replacements at 100k

 

[geeman789]

Originally Posted By: fdcg27
Sure, but there must be a marginal increase in radiated heat absorbed by the additional area of the can and it can only make the oil warmer.
That might be a good thing or a bad thing, depending upon how hot the typical NA 2.5 gets its oil in normal use.
Might actually be an advantage, but if Subaru thought that, they would have used a longer can.


A more likely scenario is that the shorter filter was $ 0.10 cheaper... !

 

[FutureDoc]

Or that a longer filter added no additional/tangible benefit.

 

[geeman789]

Originally Posted By: FutureDoc
Or that a longer filter added no additional/tangible benefit.


Except on the new engines, with the oil filter on top of the engine, they use a LONGER filter... must be some benefit, or else they wouldn't bother.

 

[FutureDoc]

Originally Posted By: geeman789
Originally Posted By: FutureDoc
Or that a longer filter added no additional/tangible benefit.


Except on the new engines, with the oil filter on top of the engine, they use a LONGER filter... must be some benefit, or else they wouldn't bother.


I run the same filter (Wix 7055/Napa 57055) on both my '99 (EJ) and '14 (FB). Basically, the EJ gets whatever I am using on the FB. The '14 specific might be a bit narrower but there are no issues running the 7055 on the EJ.

 

[fdcg27]

Originally Posted By: webfors
Originally Posted By: fdcg27
Sure, but there must be a marginal increase in radiated heat absorbed by the additional area of the can and it can only make the oil warmer.
That might be a good thing or a bad thing, depending upon how hot the typical NA 2.5 gets its oil in normal use.
Might actually be an advantage, but if Subaru thought that, they would have used a longer can.


True, but if Subaru was all knowing (or all caring) they would have used a closed deck design for the ej25 and spared us all HG replacements at 100k

Maybe if you had used the correct oil filter, the engine would have run cooler and not suffered a head gasket failure?
J/K
These engines are undeniably subject to a higher rate of HG failure than is typical of modern engines in general, but it is by no means 100%.
Some of these engines run to the car's grave without issue while some have HG failures pretty early in their working lives.
Whether this involves very specific operating and maintenance practices or is just the luck of the draw I have no idea.
Our Forester is fine thus far, but I'll bet that the one you have was as well until it wasn't.

 

[webfors]

Originally Posted By: fdcg27
Originally Posted By: webfors
Originally Posted By: fdcg27
Sure, but there must be a marginal increase in radiated heat absorbed by the additional area of the can and it can only make the oil warmer.
That might be a good thing or a bad thing, depending upon how hot the typical NA 2.5 gets its oil in normal use.
Might actually be an advantage, but if Subaru thought that, they would have used a longer can.


True, but if Subaru was all knowing (or all caring) they would have used a closed deck design for the ej25 and spared us all HG replacements at 100k

Maybe if you had used the correct oil filter, the engine would have run cooler and not suffered a head gasket failure?
J/K
These engines are undeniably subject to a higher rate of HG failure than is typical of modern engines in general, but it is by no means 100%.
Some of these engines run to the car's grave without issue while some have HG failures pretty early in their working lives.
Whether this involves very specific operating and maintenance practices or is just the luck of the draw I have no idea.
Our Forester is fine thus far, but I'll bet that the one you have was as well until it wasn't.


I didn't need to do mine just yet. It was a premature maintenance that I decided to do since I needed the timing belt done along with the release bearing on the clutch. I figured pulling the engine and doing it all at once would save me money in the long run.

There was only minor seeping happening in one spot at the time. Probably could have gone another 30k.

 

[fdcg27]

Sounds like good PM.
If you think it's coming, why not do it now and be good for another 100K as long as you have the engine out anyway?

 

[HerrStig]

Originally Posted By: fdcg27
Originally Posted By: webfors
Originally Posted By: fdcg27
Sure, but there must be a marginal increase in radiated heat absorbed by the additional area of the can and it can only make the oil warmer.
That might be a good thing or a bad thing, depending upon how hot the typical NA 2.5 gets its oil in normal use.
Might actually be an advantage, but if Subaru thought that, they would have used a longer can.


True, but if Subaru was all knowing (or all caring) they would have used a closed deck design for the ej25 and spared us all HG replacements at 100k

Maybe if you had used the correct oil filter, the engine would have run cooler and not suffered a head gasket failure?
J/K
These engines are undeniably subject to a higher rate of HG failure than is typical of modern engines in general, but it is by no means 100%.
Some of these engines run to the car's grave without issue while some have HG failures pretty early in their working lives.
Whether this involves very specific operating and maintenance practices or is just the luck of the draw I have no idea.
Our Forester is fine thus far, but I'll bet that the one you have was as well until it wasn't.
The OIL FILTER size caused an engine failure....don't make me laugh.

 

[FutureDoc]

Uggg, Subaru HG "issues".

First of all, there are two radically different "issues".

EJ Phase I - internal failure. This is for 1996-1999 EJ "Phase" Legacy/Outback engines. In the mid-90s, Subaru was left out in the SUV craze and they did not have a vehicle/engine to roll out for the American consumer. The solution, add a lift kit, some paint, and bore out the 2.2 and make it a 2.5. The problem with this was that 1 in 7(ish) engines, the tolerance was not machined correctly. Thus, a significant number of Phase I engines were potentially problematic and the HG failed... and nearly always resulted in an internal failure. Now, many of these engines go 300k without issue but because the internal fail is such a beast and harder to catch, when the failure is found it is not an easy correction. You could potentially have the failure even after it was corrected if you did not machine it during the repair.

EJ Phase II -external failure- (Forester 98-2004 Leg/OB 2000-2003/4). So Subaru went back and revised their 2.5... changed it a lot. Went SOHC as well. With this issue, it was not a manufacturing inconstancy (at least not a Subaru issue like the Phase I), rather it was a inferior part supplied via a third party. The composite HG would fail externally. Unlike the earlier failure, you can basically drive the Phase II indefinitely with the leak as long as you refill it. However, the rate of failure was extremely high... not 100% but up there. Still, after the fix (if done correctly) with a good composite or preferably metal HG, you do not have to worry about the HG again. The biggest problem with Subies is that often HG repairs were not done before a used sale or were done poorly (or they only bothered with one gasket). After 2004, while HG failures occur, they are not nearly at the same rate as pre 2004 failures. Still, if you have the same common-issue for 8 years (really two different problems) then it is hard to dodge if folks are looking for an issue. It is not like that all Subarus have two HGs that could potentially fail... wait... they do. darn!

In the end, what hurt was that the 2.2 Subaru engine was bulletproof. You could even limp it home with a toasted timing belt. SO the Phase I 2.5 is the worst engine Subaru ever built... and I have one with nearing 210K and all I have done in the last year and a half was to replace a knock sensor.

 

[Nate1979]

Run a Fram Ultra. Superior filtration and high capacity. No need for oversized with the increased capacity of the Ultra.

 

[geeman789]

Originally Posted By: Nate1979
Run a Fram Ultra. Superior filtration and high capacity. No need for oversized with the increased capacity of the Ultra.


But why not... a 7317 is basically identical to a 6607 , just an inch taller. Same basic filter, but more filter area, and the same price... and it fits fine. Again, why not go with the oversize filter...

Although, i would hardly call the 7317 Fram "oversize..." compared to anything except the stock filter. It is still SMALL.

I do now have a WIX 7055 "oversize..." on my bench... similar in size to the Fram 7317's , but with the Subaru spec by-pass...