New H6 Subaru

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Dec 10, 2006
Western CT
Taking delivery of a new 3.0R (H6 engine) Legacy in a few hours. I've done a bit of research on what oils and filters to use... (understatement!).
I'm looking for additional input on when to do the first oil/filter change, and what oil to use. As you may know, filters are problematic- maybe I'll get lucky and find some of the preferred black Toyo Rokis.
Subaru requires an initial early oil change at 3000 miles. This is unique to the 6 cylinder-engined cars. The H6s supposedly tend to shed some metallic junk when new. Maybe the long and complex timing chains layout....

My questions are these - would an early oil change (1000 miles) be worth it? I would still do the 3000 mile change to remain in warranty compliance. For a short run, what oil? Thinking higher moly....
As always, any and all advice is appreciated- thanks!
Filters should not be a problem for the H6. I believe Roki still makes the AA031. Honeywell is not making the H6 filters as far as I know. If recently produced, the 3k/3mo rule of thumb is ok. If it sat on the dealer lot for a while with unknown # of cold starts, then I'd lean to a 1k change. I happen to believe that today's engines, even with some abusive maintenance practices will far outlive the rest of the car. YMMV.
I'd go for a 1k OCI.

As far as the filters, I have a H4 and also have read the "concern" about the filters.

I use Supertech, Purolator and WIX filters with no problems. The UOAs have been ok (my Subaru likes certain oils over others) in the 25k I've had it.

I did mine at 1200 miles and here is the UOA. I don't have a chain so it "should" have less break in metals than yours.

Al - 8
Chromium - 1
Iron - 13
Copper - 10
Lead - 1
Moly - 163
Mag - 1
SI - 78

insol was .1

Anything else was zero...

If fact except for the copper and AL my factory fill was better than the last UOA I had with the engine.

I'd use any 5w-30 oil, prob either Halvoline DS, Valvoline or Pennzoil YB.

Take care and enjoy the new ride! (post photos)

People say it's not needed, but I do the 1k miles oil change on new cars. You'll be completely fine without doing it, but I personally like to do it.

I've been told by the shop at the dealership that Subaru doesn't use any break in oil, so it can be changed any time without worries. If you look at the UOA their factory fill has a very high moly count, not sure if that means anything, but figured I'd mention it.

I've also heard that factory fill is a 0w-20, that surprised me when I heard it and I didn't believe it b/c Subaru doesn't recommend a 20 weight for any of their vehicles. But if you look at UOAs of the factory fill, you'll notice that at 100ºC they are in line with a 0w-20, or 5w-20. I'm not saying that I now believe they use a 20 weight as factory fill, but whatever they use is either very thin at operating temps, or shears a lot.

Side note, the H6 is an excellent engine. Subarus are known for being very reliable and the H6 is extremely reliable. Some people even argue it's the most reliable engine Subaru has put out, claiming it's more reliable then Subaru's old 2.2L 4cyl which was known to be bullet proof.

The only thing with the H6 is the filter sits on sides ways, which isn't a big deal but I just like to pre-fill my filters. The one major complaint you'll hear though is that changing the spark plugs is a major pain.

I know it's a long ways off, but if you think you'll do the plugs yourself, I suggest you first read this: and this:
No problems ever with using the SuperTech filter on my SVX. I would do the 1K change with the oil only. Maybe a couple shorter OCI's using any of the quality semi-synthetics (and I include the DS, CoNoCo siblings, etc. in this category) and then go to PP or SynPower down the line if you want to go to longer intervals.

Subaru H6's are VERY reliable engines: at least the 3.3L from the SVX era is!

Plug changes can be challenging, on the SVX the battery, air cleaner housing, etc. need to be removed 1st. Having the correct length socket extensions helps, too. NOTHING in comparison to changing the valve cover gaskets!

Thanks for the replies!
Brought it home mid-day, uneventful 52 mile trip. The family absolutely loves it... including the color (seacrest green). Guess Dad did good....
For posterity- the parts manager knew all about the filter concerns. As it turns out, the H6 filter, for now, isn't a Honeywell/Fram. It is a Tokyo- not Toyo- Roki, p/n 15208AA031, as per Wagonboss, and labeled "made in Japan" in several places. Dome end ADBV/bypass, orange colored seal just visible. I purchased 8, with crush washers.
The parts guy also gave me a heads-up regarding the drain plug crush washer- he received a SOA bulletin warning about improperly made aftermarket & imitation washers have caused some severe leakage problems, including fallen-out plugs.
Originally Posted By: PineMountain

The parts guy also gave me a heads-up regarding the drain plug crush washer- he received a SOA bulletin warning about improperly made aftermarket & imitation washers have caused some severe leakage problems, including fallen-out plugs.

Sounds like something a dealer parts guy would say. Never heard that before. I and many others have used aftermarket crush washers with no problems.

And congrats on the new car!
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Nice engine! Stay away from the high molyDTC oils if you dont want to see high Cu in your UOA, as they are corrosive in a high % add. AFA Moly in UOA, The car uses Moly coated piston slippers and this shows in the oil along with any moly assembly lubes. Use Conventional with ~4K oci and you should be OK. Subarus tend to like higher vis oils. My new Forester needed a 40wt spike to stop piston slap. The Service replacement Honeywell 12A is a well made filter for the 4cyl, no need to trash it, it doesnt leak as does the puroleaker and the wixapissa - the best 2 commonly available aftermarket units. That said, I would choose the T-R for long interval OCI's, it is clearly made BETTER than the Honeywell. Good luck and enjoy your subie!
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I would personally like to see an "imitation" washer?

This ain't rocket science, boys & gorls!

My wife drives an 06 Tribeca with same almost has 50,000 miles and only mechanical issue has been one bad oxygen sensor. Engine is great but seems to use about 1/2 quart of oil every 5,000 miles. We leased it and have now bought it so I have to admit I have been more careful about change intervals. Last change was Pennzoil YB and this change was Pennzoil Platinum with a Motorcraft filter.
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