Post HPL Cleaner; 17 Outback 7500miles Mobil 1 EP 5-30; 168k 3.6

[BISCUT]

Started this thread back in January 2024. 1 Quart of HPL Cleaner was used for IIRC 5500k mile run. I've had the 3.6 Outback since new and have only used Fram Ultra filters. First one to be wavy was the HPL run. Below are images of my recent OCI of 7500 miles with Mobil 1 EP 5-30. Filter looks good like all the other ones I've cut , besides the HPL run. Also attached is a UOA.

Did the HPL cause the wavy pleats? What happens when you introduce HPL cleaner to an OCI? Can't wait to hear the responses.

Previous thread:
https://bobistheoilguy.com/forums/t...pl-cleaner-and-post-hpl-oci-5200miles.377578/

 

[fantastic]

Well, the biggest difference between most of your previous Fram Ultra's was that they were wire backed. Now that they are no longer wire backed your seeing a common trait associated w/them now. Doesn't mean everyone will be wavy but the chances are much higher now. I doubt it has anything to do with HPL 30. All that being said the pic you show doesn't reflect any waves I can see (look straight).

 

[OneLonelyBurrito]

FYI its doesn't look like your UOA is posted. I'm only seeing the picture of the filter.

 

[himemsys]

I agree with the other two. I don't see wavy pleats in the picture you posted, and I don't see a UOA.

 

[twX]

High dP across the filter media probably contributes to the wavy pleats seen in your previous post. If the HPL did any cleaning, the filter may have been pretty loaded up. What clogs filters is the very small stuff embedded in the pleats, usually carbon. Just because there are no large chunks of visible carbon doesn't mean that the HPL didn't do any cleaning, or that the filter isn't loaded up.

If you dry the media out really well by leaving it wrapped in paper towel for at least a day, and the media still looks really dark, it's probably pretty loaded up with carbon.

These 3.6L engines have very high output oil pumps, rated at 83 L/min, compared to 46-55 L/min for the non-turbo 4-cylinder Subarus. The OEM filters for these engines have a lot of media area (1300 cm^2), 50% more media than the filters for the 4-cylinder engines, and over twice as much media area as the XG9688.

FRAM specs the same XG9688 for the 3.6L as they do for the 4-cylinder engines that have much lower oil flow rates, since they'd rather not make a special filter just for this engine like Subaru does, and it's woefully undersized for the application. I'd expect there could be over 20 psi of pressure across the media on this filter even when the 12 psi bypass valve is wide open, which it will be at high rpm.

 

[hemioiler]

Well, the biggest difference between most of your previous Fram Ultra's was that they were wire backed. Now that they are no longer wire backed your seeing a common trait associated w/them now. Doesn't mean everyone will be wavy but the chances are much higher now. I doubt it has anything to do with HPL 30. All that being said the pic you show doesn't reflect any waves I can see (look straight).

FYI its doesn't look like your UOA is posted. I'm only seeing the picture of the filter.

I agree with the other two. I don't see wavy pleats in the picture you posted, and I don't see a UOA.

The wavy pleats are in the thread he linked in his first post, this one here:
https://bobistheoilguy.com/forums/t...pl-cleaner-and-post-hpl-oci-5200miles.377578/