Mobil 1 10W-30 for 17,000 miles - data arrived!

[SD_GR]

I've been following this site closely:

http://neptune.spacebears.com/cars/s.../oil-life.html

Basically, they take an LS1 in a Camaro (irrelevant, it could be any other car really) and break it in, then they switch to Mobil 1 5W-30. This is the same ACEA A5 oil you and I can buy (and yes, I do, I'm running M1 10W-30 now and use 5,000 mi drain intervals).

They run the car as usual, winter/summer/whatever, and take oil samples every 1,000 miles. They then post the analysis data. So far, they've gone 17,000 miles on the Mobil 1 and are doing quite well! Amazing.

The reason I've posted this even though I've mentioned it before is that they might finally change the oil (!) and I don't know if the oil analysis data will continue to be posted on their site. If you're an oil hobbyist, it's a must-see; if you're only interested in a good oil for your WRX, it's definitely worth a visit to the site.

Although the LS1 is normally aspirated, it does produce adequate power considering the large displacement, and owners tend to push their cars. Plus, it has a reputation for burning oil and/or piston slap, so there are definitely parallels to be drawn between the testers and us IMO. Have a look guys!

Cheers,
SD

[AREITU]

I've read that before. I think that should be made a sticky, or at least placed somewhere for easy reference whenever someone says synthetic is just a tactic to make money.

[SD_GR]

Agreed. I think their attitude says it all actually - they're not changing the oil because they have to, they're changing the oil because it's getting boring! They've had it in for almost a year at this point and they want to switch to another brand of synthetic to see how well that one does instead.

I think they could swap filters, top off with 1 qt fresh Mobil 1, and probably go on for quite a bit more frankly. This'd probably put their TBN and wear numbers at the same level as they were at ~10K miles.

I am feeling quite comfortable with my chosen 5,000 mile drain intervals at this point. With my mellow driving style and freeway conditions, I think Mobil 1 could easily take me to the full 7,500 miles permissible by Subaru's warranty requirements, so I'm leaving myself a good ~30% margin of slop/safety. This ought to account for some of the differences in specific output (and thus stress) between the LS1 (55HP/L, same as a 1980s Autobianchi...) and the EJ205 (113HP/L).

The oil's flashpoint has dropped quite a bit, leading me to think that it's not the greatest idea to leave that oil in a turbo motor for the same amount of time, but 5,000 ought not be a problem considering their flashpoint data at twice that mileage is still adequate (again, I'm guessing to compensate for their lack of a turbo and all the associated thermal/mechanical stress on the oil).

[JRod]

Definatley reassuring data, but I'll stick to my 3K mile interval with Mobil 1. Plus I'm using a SUS air filter which could ingest some very small particles into my engine/ oil.

[shadowfaxwrx]

great read, thanks.

[wrx666]

Hi SD,

Thanks for the link. I find much of the Neptune site interesting.

But i have to ask... If this M1 oil is kicking so much butt (in this guy's Camaro, at least), why do you change your oil at 5K, and not the 7.5K as mentioned in our user's manual? I look forward to your insight.

Thanks!

[SD_GR]

My main concern with the EJ20 is the oil routing to and from the turbo. The LS1 GM motor may make more power, but has a specific output much lower than the EJ20x series. Another concern I have is that my particular car is sometimes driven in a high dust environment, and that I live in a relatively hot climate (southern California, inland).

I do 5,000 to give myself some additional margin. I could conceivably do an oil analysis at 5,000 to see what's going on and confirm whether I could go longer than that, but I'm not that organized! Plus, doing multiples of 5 makes it ultra-easy to remember when to change the oil, and to remember when to rotate tyres and check the undercarriage every second oil change etc.

I'd not go the full 7500 without an oil analysis at 5000 or so just to make sure, since motors and conditions and driving styles vary so widely.

There is a rumour that Mobil are pushing for their M1 5W-30 and 10W-30 to meet ACEA A3 just like the 0W-40 and 15W-50 grades do. If this actually happens I'll seriously consider going 7500 miles between changes while under warranty (currently 10W-30 is "only" ACEA A5 - still quite stringent!).

Still, reading between the lines in our owner's manual, it seems Subaru are confident their motor will last 60,000 miles with 7,500 mile oil drains if driven conservatively in a decent environment, using *any* API SL oil, be it good or barely adequate. The issue is really what can be done now to make sure the car goes well beyond 60,001 miles (end of warranty) with as little trouble and as little waste as possible.

I have read posts from others that use M1 and go 5000 like I do. This data and other stuff available on various sites makes me think we'll all be quite safe.

EDIT on 2003-07-OCT: They finally changed the oil at 18,000 miles. They're doing a flush period of about 2K miles with their next oil, Amsoil 5W-30, and then starting the study again with that oil instead. It'll be really interesting to see what happens to the motor in the next 2 or 3 years of use; that study is a landmark!

[wrx666]

Hi SD,

Thanks for the reply. As i've said before, i respect your opinions as they are usually backed up with fact, or at least factual speculation, ha!
Really, thanks for all your posts on this board.
Tu eres el hombre!

[SD_GR]

wrx666, your kind words inspired me to look more closely; here's a link to someone that has done just what we're talking about: taken a WRX 2.0 US turbo motor to 7500 miles on Mobil 1!

http://theoildrop.server101.com/ubb/...=000844#000000

I particularly liked the discussion in that thread, because they complement our motor (oh, vanity...). Seriously though, it seems like Subie have a solid motor. I don't think it'll fail under normal use and with adequate maintenance; I now think the real issue is going to be we'll either get bored with our cars outright, wreck them, break the driveline, wear out the interior, or go insane from all the rattles in the cabin. The motor will hold IMO!

While you're on that site, do a search for WRX. Oil analysis data using Redline and other oils will also pop up -- quite interesting.

Thanks for the discussion and cheers!
SD

PS EDIT: If the analysis poster, DAVE, is on this board, thanks and let us know you're here OK?

PPS, EDIT2: Or any of these fellow WRXers:
http://theoildrop.server101.com/ubb/...=000718#000000
with their Mobil 1 analysis data, are you guys here too? Hi!