Rottella T6 3400 Miles, 2004 forester XT

[Txgsx87]

Here is my report on my bone stock 2004 forester XT. Had a puralator pureone on there as well, which I cut open and it looked perfect. Tempted to try mobil 1 0W-40 next, to see if there is much of a difference. Also running RT6 in my bolt on Evo X which I need to send a sample in.

 

[Garak]

I bet with a TBN of 7.1 at 3400 miles, one could go a long way on this oil.

 

[yvon_la]

Might want to try t6 0w40 ,it sound the same but its supposedly a different formulation .formulating a 0w40 for big truck ,men shell engineer really are passionate.when my warranty expire I ll move to t6 0w40. PS:is this uoa one of the better looking ,number wise?must be in the top if it isn't the best .I'm happily surprised

 

[toneydoc]

That oil had a lot of life left in it. Could easily go double those miles without a thought.

 

[Garak]

As with Mobil, the Rotella 0w-40 will have a lower starting TBN. Oddly enough, Rotella 5w-40 doesn't list E7 (the higher TBN mid SAPS spec) that Delvac 1 ESP 5w-40 has, but certainly has sufficient starting TBN. Well, there we go to the naysayers about mid SAPS HDEOs. After 3400 miles, TBN is still 7.1 Blackstone's 5500 mile recommendation is a bit conservative, I suggest.

 

[abycat]

I bet 15000 would be easily attainable.

 

[ARCOgraphite]

Why not a high HTHS 30 grade ACEA A3B4 to loosen up some power?

 

[Txgsx87]

I'm open for other suggestions. I'm in Houston so generally pretty warm all year around. I've only owned this car for 10k, but for sure I'll be doing longer intervals.

 

[Garak]

Originally Posted By: abycat

I bet 15000 would be easily attainable.

I'm thinking you may be right. By the way, did you leave BC, or am I hallucinating and you were never from there?

 

[bluesubie]

Originally Posted By: abycat

I bet 15000 would be easily attainable.

No way! Subaru recommends 3,750 miles intervals max on this model year, even with synthetic, due to possible sludge blockage in the AVCS and turbo banjo bolt screens. That said, 6k on RT6 or M1 0W-40 is probably a piece of cake. But I wouldn't push any oil past that regardless of any uoa results if the OP is still running the screens. Been there, done that and it cost me $2,000. Perhaps the OP would be happy to test an oil at 15k mile intervals if bitog members pick up his repair bill! -Dennis

 

[ThirdeYe]

Wow! That oil looks like a great fit for your Subaru. Nice.

 

[Garak]

Originally Posted By: bluesubie

Subaru recommends 3,750 miles intervals max on this model year, even with synthetic, due to possible sludge blockage in the AVCS and turbo banjo bolt screens.

Yes, but they base that on a normal ILSAC rated conventional, not something that meets significantly more stringent specifications, like this example. This is what UOAs are for. Forget a plus/minus of a couple PPM of iron, and pay more attention to shearing and TBN. With this sample's TBN being higher than plenty of virgin samples of "regular" oils, 3750 miles can be easily exceeded here. One may argue that 15000 may be too long (we'd have to see on that), but there's lots of room here. If the UOA results are being dismissed out of hand, there's no point in reading the UOA, much less obtaining one in the first place.

 

[bluesubie]

Originally Posted By: Garak

Originally Posted By: bluesubie

Subaru recommends 3,750 miles intervals max on this model year, even with synthetic, due to possible sludge blockage in the AVCS and turbo banjo bolt screens.

Yes, but they base that on a normal ILSAC rated conventional, not something that meets significantly more stringent specifications, like this example. This is what UOAs are for. Forget a plus/minus of a couple PPM of iron, and pay more attention to shearing and TBN. With this sample's TBN being higher than plenty of virgin samples of "regular" oils, 3750 miles can be easily exceeded here. One may argue that 15000 may be too long (we'd have to see on that), but there's lots of room here. If the UOA results are being dismissed out of hand, there's no point in reading the UOA, much less obtaining one in the first place.

I wasn't using an ILSAC rated conventional either. Anything in this uoa to indicate impending turbo failure? Very little shearing and excellent TBN. http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1587540&page=1 That was my last run on a <3.5 HTHS oil and my last run over 6k miles. That turbo had only about 20k miles on it as well because the original turbo was replaced due to oil getting past the seals. Edit: Wow, I just noticed that I didn't change the oil filter on that run! That was based on what another Subaru turbo owner was doing at the time (under advice based on Dyson analysis). I guess you get what you pay for. Although my Subaru tech did think that the failure wasn't oil filter related. -Dennis

 

[Garak]

Is there any indication the failure was oil related, either? Of course, there's no indication in the UOA that your Turbo was going to fail. Perhaps an HTHS => 3.5 might have been more suitable. Perhaps it was a defect in the turbo. If the oil is suitable for continued service, particularly many, many more miles of continued service, and that's been demonstrated by UOA, and we ignore that advice, then we're being silly and wasting money both on the UOA and the lubricant. No one needs a UOA to tell them that T6 is good for 3400 miles. Doug Hillary, if you're reading this, what were the OCIs with Delvac 1 on your Benz, Porsche, and Cappucinos?

 

[bluesubie]

IMO, it was a defect in the design of the oil system (or maybe the oil recommendations). This site has some info as well as the TSB's from SoA: http://store.forcedperformance.net/merchant2/merchant.mvc?Screen=Info_SubaruOil And because of this, Amsoil doesn't even recommend exceeding any of Subaru's intervals on any Subaru turbo.

Quote:

Subaru has published Service Bulletin # 02-103-07 that identifies a factory design related problem with premature clogging of the oil mesh screen located inside the oiling system that supplies the turbo charger on all model turbo charged cars. A clogged screen will result in oil starvation and turbo charger failure. Subaru has since published Service Bulletin #02-110-10R indicating that 2010 MY and prior turbocharged engines continue to require oil and filter change intervals of 3,750 miles (6,000 km) or 3 3/4 months, while all 2011 MY turbocharged engines have returned to the original requirement of 7,500 miles (12,000 km) or 7 1/2 months, and they are required to use synthetic oil. Due to the issues outlined in this document, AMSOIL recommends following Subaru drain interval recommendations.

Here are details of the 3,750 mile interval:

Quote:

Due to heat generated by the turbocharger and carbon deposits contained in exhaust gas, the oil in a turbocharged engine will deteriorate faster than the oil in a naturally aspirated engine. Therefore, special care should be taken to use the proper grade oil and to monitor oil deterioration. Under normal driving conditions, the recommended oil and oil filter change interval for turbo vehicles is every 3,750 miles or four months, whichever comes first. However, for vehicles driven in conditions beyond normal, such as racing conditions, the oil and oil filter may require more frequent changes.

http://drive2.subaru.com/Sum08/Sum08_Turbo.htm This is all before Subaru recommended synthetic. And there were lots of cars that had turbo failures that were dealer serviced at 3-3,750 mile intervals. -Dennis

 

[Garak]

In the case of a potential defect in the design or the oil recommendations, I would expect Amsoil (and everyone else making a lube within specs) to specifically request that the severe service intervals be followed. That lets the oil company off the hook, unless their oils are proven faulty. However, I doubt Rotella 5w-40 is too thin, and unless 5w-40 is specifically called for in the manual, Shell wouldn't offer any warranty for its use anyhow. So, I see no benefit in very early changes using the product, and little risk in extending OCIs with a premium product and UOAs. Changing the T6 every 3750 miles is certainly acceptable, if that's one someone wishes to do. But, I don't need to spend $25 to $40 to tell me that an HDEO with a TBN in excess of 10 will survive such an OCI in a gasser.

 

[webfors]

Excellent report! Could easily stretch it out, but if warranty requirements don't allow then @ $22 a jug for RT6 it's not the end of the world.

 

[abycat]

Originally Posted By: Garak

Originally Posted By: abycat

I bet 15000 would be easily attainable.

I'm thinking you may be right. By the way, did you leave BC, or am I hallucinating and you were never from there?

sorry buddy didn't see your post. left cause of the money. love it here! Nice place.