I cut open a FRAM Ultra XG3593A that was used for 7,000 km on a 2015 Subaru WRX. The car has been on a steady diet of Pennzoil Platinum since new. It's got an unconventional lean-burn engine tune, with AFR as high as 17.5:1 at cruising loads, and normally runs on 87 octane E10 instead of 91. I've put around 55,000 km on the engine with this tune. I'm not completely sure how the lean burn tune affects things like carbon buildup, soot production, etc, so I thought maybe the oil filter would provide some clues. I may do a UOA at the next oil change.
There was hardly any visible debris in the filter, aside from a large black chunk of something, about 5-6 mm long. It's very soft and feels like foam. It's not brittle at all goes back to its original shape after being folded over on itself. Any ideas as to what this is?
There were also a few tiny specs of metal that could be seen glittering in bright light, some are ferromagnetic. I did mangle the filter can when I cut it open, so some of it could be from that.
I installed a new PurolatorOne PL14615 with a proper 25 psi bypass setting, since the FRAM Ultra will bypass some oil on this engine, and I'd rather not have big black chunks of mystery material getting into my oiling system and clogging anything.
There was hardly any visible debris in the filter, aside from a large black chunk of something, about 5-6 mm long. It's very soft and feels like foam. It's not brittle at all goes back to its original shape after being folded over on itself. Any ideas as to what this is?
There were also a few tiny specs of metal that could be seen glittering in bright light, some are ferromagnetic. I did mangle the filter can when I cut it open, so some of it could be from that.
I installed a new PurolatorOne PL14615 with a proper 25 psi bypass setting, since the FRAM Ultra will bypass some oil on this engine, and I'd rather not have big black chunks of mystery material getting into my oiling system and clogging anything.