Hi, Rick.  When you say "OEM" filter - is this a brand name?  In my
business, (electronics), it means Original Equipment Manufacturer.  So
maybe, you're talking a Subie Filter?

Hi,

I haven't a clue why some Subies, 'specially many late-'80s/early '90s
models, are so grumpy about oil filters, but many have reported their
lifter noises disappeared when using OEM filters.

On my '90 Loyale, I'd get zero lifter noise (past just a couple of
seconds on a cold start) w/ OEM. Also had good luck w/ Bosch and Wix
(NAPA Gold is the same filter in a different box.) Although I've used
plain ol' orange Frams (don't start, guys!) for years w/ NO problems in
other makes, my Subie would pitch a ring-tailed fit w/ anything from
Fram (including the "better" grades.) Lifter noise would go as long as
10 minutes before settling down.

Rislone and Marvel Mystery Oil have also produced positive results in
these engines for many users. I've used Rislone personally, about every
3rd oil change (near the end of the change cycle, maybe 500 miles to go)
and it appeared to get a fair amount of crud out of the engine when I
first got the car (209k miles of "less than perfect" maintenance by the
original owner) but after two or three treatments, I didn't notice much
difference.

Hope something here helps your car...

Rick

My 93 Legacy Turbo has had the same valve lifter rattle for the last
10 years, (& +130K miles).
I've tried just about everything I can find on the net over the years
including removing the valve cover and an oil galley plug to clean.
I've read recently that the problem is down to the oil filter which
seems to be corroborated by the noise being much less or absent just
after an oil change.

What's the advice on a high flow/efficiency oil filter?