Rotella T in my cummins, my Subaru, and my Yamaha?

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I have always ran rotella T 15w-40 in my Cummins 12 valve. I have recently read about countless people using it in their Subaru WRX's and other gasoline engines with great success, and also reading about folks using it in motorcycles and atv's with wet clutches that run in the engine oil. So, I have decided to start running it in my 2002 Subaru WRX, and also in my 2008 Yamaha grizzly 700 ATV. I read that it was JASO certified and is excellent for motorcycle/atv engines. Does anyone think this is a good or bad idea? And if so, exactly why? Keep in mind I am not concerned about damaging my catalytic convertor, so I don't want to talk about that or fuel mileage. I am concerned with wear protection, and engine protection for longevity, not mileage and saving my convertors. I get the impression that automotive SM rated oils are [censored] compared to rotella, in terms of engine protection. Is this true as a general rule of thumb? And since I am trying to draw conclusions on which oil's offer better wear protection, what is the best tools (or method) to do that? Should I look at the oil contents to compare oils? More ZDDP etc? Or should I look at oil analysis' of different oils? What is the best way to determine the better oil for me? I want oil that offers the best protection, not the best mileage, not the safest for the environment, etc. I am not out to please Al Gore of fill his pockets, just protect my engine. Thank you! Joe
 
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It's not a bad idea. I think you have a bit too much focus on wear. Any oil you use in the subaru will provide a million miles of wear protection if changed properly, there isn't really significant differences in wear between oils (unless you consider the M1 iron controversy) and you won't be able to statistically prove one with UOA. The differences will be considerable in the condition of the oil over time, it's ability to fight deposits... etc. In that car, I would be most worried about deposits on the turbo, and an oil's ability to handle the heat. What does the WRX call for? I wouldn't want a 40 weight dampening the fun of a high revving engine just to not have to stock two grades. You can get a nice syn SM 30 weight, save your 02's and pour it down a sewer drain when you're done to spite Al (I don't have the energy to debate you on this).
 

Mad_Engineer

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It calls for a 5w-30 oil. Do you really think switching to syn 5w-40 would dampen it? Many people run it on the subaru forums and swear by it. The 5w-40, (5w part) will offer protection at cold starts, similar to the 5w-30 recommended, correct? Is it true, as a general rule of thumb, that heavier viscosity oils protect better? I am also interested in comments from people running this oil in their motorcycles, or atv's. And I do take my oil to recycle, but I can see how one would want to spite Al. Thanks, Joe
 
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I have run it on my EX500 with no problems, for about 1500 miles a year for two years then about 400 miles last year. No significant difference in cold starts over a 10w-40 that I had been using beforehand which was a disappointment (cold start for that app would be about 40 degrees, but it is a cold blooded creature) but the shift quality was retained longer. "is it true, as a general rule of thumb, that heavier viscosity oils protect better?" That is a great debate you could read for days on, and there are a lot of generalizations thrown around. I would say the difference between a 5w-30 and 5w-40 in a vehicle that calls for a 30 weight there will be no measureable difference. While the 40 weight has better hightemphighshear (good), it also has a higher viscosity index (bad). Too many variables. Will it dampen it? I don't know. Give it a try and tell us! There's nothing to lose.
 
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High viscosity index is good. That means that the oil thins less when hot and thickens less when cold. The viscosity index is determined by the oil's viscosity change from 40°C to 100°C. Rotell-T isn't certified for JASO-MA, just that Shell has run it through the tests and it passed. That wasn't official, but plenty good enough for me. MA is the wet clutch motorcycle spec for the Japanese Automobile Standards Organization.
 
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"High viscosity index is good. That means that the oil thins less when hot and thickens less when cold. " Ok. Sounds good. But is that all it means? All things equal, an oil with a higher VI will have more viscosity index improvers which is not good for a number of things, resistance to shear comes to mind. Rotella doesn't have high rates of shear, but I've seen comparisons to some Amsoil products like SAE 30 that blow it away. Everything is a compromise of some sort. Then again, the original poster is right, there are a lot of positive reports of the 2.5 on rotella. Maybe for him the planets aligned and he can live the dream of buying 55 gallon drums of Rotella 5-40.
 
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dnewton3

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I cannot comment on the Subie, because I don't have one. But I do run dino HDEO in much of my equipment, be it gasser or diesel. That includes many of my shared-sump bikes over the years. You'll find excellent performance from the new CJ-4 dino HDEOs; very cost effective protection. Shop around, and you might even be able to find them in the lighter grade, as I do. Rotella 10w-30 is in my 2006 Duramax truck, my 1966 289 Mustang, my air-cooled lawn equipment, my Kubota tractor, and will likely find its way into my Goldwing once my stash of 5w-40 RTS runs out. Being in SC, you could likely get away with running the 15w-40 grade year round.
 
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 Originally Posted By: Mad_Engineer
It calls for a 5w-30 oil. Do you really think switching to syn 5w-40 would dampen it?
Have a look again. 5W-30 is preferred for fuel economy. 10W-30 and 10W-40 are allowed in higher temps. 50 grades are even allowed in severe conditions. I couldn't tell much, if any difference, when I switched from a 30 grade to a 40 grade. Then again, I have a 2.5T so that might help with turbo spool-up and engine response. I say go for it! -Dennis
 
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I run Rotella T synthetic in my Subie and my Yamaha. It works great! My UOA's show I still have some additive left even at 7500 mile OCI's. It is fine to run with the wet-clutch as it is not "Energy Conserving II," per Yamaha.
 
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I have 40,000 kilometers on my zx6r with rotella 15w40 and it runs like a dream and doesnt burn oil. Those are hard hard kilometers with lots of red lining and such. Tough stuff.
 
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a 5w40 might not have more VII's than a 5w30. It just depends on the base stocks used and how close to the edges of the specs they are. a 5w40 might be thicker at -30degrees but still in spec and a 5w30 might be almost as thick as a 40weight at 100degrees. once you get into 5w50 and other wierd grades I'd have to agree they do have more VII's high viscosity index by itself is a good number.
 
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Go for it! Reading between the lines in the owner's manual of our NA Subaru, I get the impression that the engine really prefers a little heavier oil. Turbo Subies seem to do well on this oil, judging from the UOAs posted here. It won't hurt the diesel (naturally) and many bike guys swear by the oil. I have run the 5W-40 a number of times in our Ford Vulcan and you really wouldn't know that you didn't have a 5W-30 in it. Shell uses a Grp III basestock with a high natural viscosity index for this oil, so I think that the VII load is probably very light.
 
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Originally Posted By: Mad_Engineer
I read that it was JASO certified and is excellent for motorcycle/atv engines.
This is false it is not JASO certified. But it apparently pass the fiction test. Thats said Rotella will work fine in your bikes/atv's.
 
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Originally Posted By: bepperb
Maybe for him the planets aligned and he can live the dream of buying 55 gallon drums of Rotella 5-40.
slobber I'm thinking of running Rotella's 5w40 in my Subie when my stash of PP runs out... only another 60k to go drive Great oil for a Subie, turbo or NA.
 
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Originally Posted By: heavyhitter
Originally Posted By: Mad_Engineer
I read that it was JASO certified and is excellent for motorcycle/atv engines.
This is false it is not JASO certified. But it apparently pass the fiction test. Thats said Rotella will work fine in your bikes/atv's.
Did the Rotella fail the test or was the Rotella not tested?
 
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Originally Posted By: Steve S
Originally Posted By: heavyhitter
Originally Posted By: Mad_Engineer
I read that it was JASO certified and is excellent for motorcycle/atv engines.
This is false it is not JASO certified. But it apparently pass the fiction test. Thats said Rotella will work fine in your bikes/atv's.
Did the Rotella fail the test or was the Rotella not tested?
I have seen post from Rotella saying that they tested the oil and it passed the JASA MA friction test. But Rotella is NOT JASA MA certified. If that is because they do not want to pay for the label or whatever I do not know, but it is not "certified" unless something has changed that I am unware of. The "label" or lack there of means squat to me.
 
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Originally Posted By: heavyhitter
Originally Posted By: Steve S
Originally Posted By: heavyhitter
Originally Posted By: Mad_Engineer
I read that it was JASO certified and is excellent for motorcycle/atv engines.
This is false it is not JASO certified. But it apparently pass the fiction test. Thats said Rotella will work fine in your bikes/atv's.
Did the Rotella fail the test or was the Rotella not tested?
I have seen post from Rotella saying that they tested the oil and it passed the JASA MA friction test. But Rotella is NOT JASA MA certified. If that is because they do not want to pay for the label or whatever I do not know, but it is not "certified" unless something has changed that I am unware of. The "label" or lack there of means squat to me.
I've used Rotella T triple protection formula in all my yamaha atv's. I have a copy of a letter from Shell reading that the triple protection 15w-40 meeting the low ash level that would make it equivalent to meeting JASO specs. It also states it is wet clutch safe. I've never had a clutch go bad on any of my bikes. I save some $$$ using Rotella over Honda oil or Yamalube.
 

gathermewool

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I'm on my second run of RTS in the '08 STI, and just switched to RTS in the '97 Legacy. It's a good oil, and I really like only having to stock one oil for both cars!
 
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