Rotella T5 15w40 grade

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Jan 12, 2008
....I see it really does exist! Saw it today at autozone in bay city,MI. This T5 was in the past only available in a 10w30 grade. Not that im exactly jumping to buy this oil..and analyze it and post results here (that gets rather expensive)...but I heard rumor about this oil on this website, and in general "diesel talk" conversations without actually seeing for myself until today. Priced about 5 dollars more per gallon than the regular dino version. I ran a batch of regular triple protection rotella 15w40 hard for 9,000 miles with stellar results in my LBZ duramax. The viscosity was starting to thicken a bit...but everything else was fine. I have heard many folks outside of this forum talk about rotella being a "decent" oil...but having problems with oil consumption? Perhaps this oil is tailored to help with this as I see in the spec sheet a higher flashpoint compared to the regular dino version. Lower pour point obviously also. I'd like to mention like fellow respected member Dnewton3 has quoted many times before in his own way...that "just reading specs does NOT determine the outcome of the oil in the end". Have a nice day fellow oil guru's.

I'm not sure what the reasoning would be, other than to compete with Mobil Delvac Elite 15w-40, or vice versa. Was this oil dual rated? The Delvac Elite 10w-30 is only CJ-4, while the 15w-40 is CJ-4/SM.
For the Dmax, Ponch, the official GM oil consumption rate considered to be "acceptable" is one quart per 100 gallons of fuel consumed. This will depend upon how heavy you're towing or lightly you're loaded.

When I'm unloaded over several thousands miles, I don't consume any oil whatsoever in my Dmax. When I'm running hard in the heat of summer, WOT uphill pulling the RV, etc etc, I do consume some oil. However, my Dmax has never got to the point of consuming 1 qrt / 100 guel gallons. At least not yet.

Food for thought.
And I think I remember seeing that the T5 is on sale at the same price of T6 at AAP now. That sale ends in a couple or weeks IIRC May be an opportunity to buy some if you are so inclined or want it
Yes dnewton3 I did indeed forget about GM's spec on consumption.. I never had much of an issue with that no matter what weight I ran..the consumption rumor I heard from other forums. To answer "garak"...I believe I only saw the CJ-4 certification on bottle. I don't recall seeing any SM certs.
Thanks for the info. A couple of these oils are having strange ratings for little discernible reason. Then again, there really isn't a huge need for an SM or SN rated 15w-40 in North America, although some of us like to have the dual ratings confirmed.
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