Shell Rotella T6 Synthetic 5w-40

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Does anybody know if this oil is a group 3 or group 4 base stock? I really like this oil. It gives me a little more oil pressure for summer temps. My 4.7 runs just as smooth and peppy as it did on 10w-30. I've tried 15w-40 in the past and the engine felt sluggish.
 
Originally Posted By: BobFout
It's a group III+.


I don't really know what that means, as opposed to any other designation, and I've been around here a long time.

To say that it's "group III+", would infer that it's somehow "better" than group III? Would someone say that Mobil 1 is "Group IV-" (minus) because it has some marginal amount of base oils other than PAO?

Nearly all lubricants available commercially on the mass market are "blends". They are not "pure", but rather a maturation of primary and secondary base stocks, with differing additives packages, all based upon the consumer and/or vendor goals.

T-6 is a group III product; severely hydro processed oil. It's got quite a bit of VII to get such a broad grade range. I do know that it performs quite well, typically putting forth stellar UOAs. I'm not confident whether it has PAO in it or not; but I don't really know that it matters, either. I guess knowing the "inputs" of an oil makes for interesting chatter, but the "results" are MUCH more telling of a product's capability. Would you rather know the starting roster of a base-ball team, or the final score?

It's not "perfect", but no oil is. It's a good fit for a wide variety of applications and has a good performance/dollar ratio. It is primarily thought of as group III.
 
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Here is 5-hours of track time on my turbo miata with 250* oil temps on Rotella T6 Synth
54yx38.jpg

Forget the base-stock designation, this oil works.
 
Originally Posted By: BobFout
Dnewton, the Evolution section here explains it.

http://www.machinerylubrication.com/Read/533/base-oil-trends

Googling for group III+ also nets some more info.


My apologies; wasn't trying to pick on you; not my intent.

It's just that, like I said, there is no "pure" oil; they all exist with some secondary base stocks and varying additive packages. No one ever dares to refer to Mobil 1 as a "Group IV-" just because it has some lower base stocks in it to help carry the additives. Mobil 1 is not PURE PAO, but we all consider it group IV. It's a manipulated oil product just like T6, Edge, Synpower, and everything else.

Is a group III+ the "same" as a group IV-? We've heard of group II+, but would that be much different than a group III-? Are we splitting hairs so thin? Are we even concerned about the percentage of each base stock used? What makes something a "PAO" when it may have 51% group IV, but if it only had 48% group IV, what would it then be called?

Conceptually, it's like debating the merrits of a "C+" versus a "B-". The distinction is there, but it's so whacked and overblown because the you also have to include the sub-topics to give it frame of reference.

The reality is that marketing folks will never want well defined descriptions with % content on their product labeling; that would make it too easy to know what you're buying ...

I makes litte sense to keep sub-dividing the subdivisions ... Perhaps it's time for the lube industry to redefine the entire class description system.
 
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I didn't take it as a picking, just an honest question. I too had never heard of III+ until I saw Johnny post about it regarding RTS and/or T6, sometime last year.
 
Well, you certainly have educated me on a new topic. Thanks!

OTOH, I still don't like the way products are sub-labeled. It is ambiguous at best. But I also understand that I'm not the only person they market to.
 
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Did anyone catch the statement about how all major oil companies are rapidly switching their automotive oils to these groupIII base oils? That would include I suppose EOM who is the producer of M1.
 
Hey Hustler, any ideas on that 1.8% fuel dilution? I thought your vis was low for a moment, but I'm sure your Miata doesn't have a large sump, so 1.8% of gasoline would probably bring you down to 30wt...
 
Originally Posted By: D-Roc
Hey Hustler, any ideas on that 1.8% fuel dilution? I thought your vis was low for a moment, but I'm sure your Miata doesn't have a large sump, so 1.8% of gasoline would probably bring you down to 30wt...

You are correct. I hold about 5-quarts. The oil dropped to about a30wt. I leaned it out a lot in cold start and fuel dilution reduced considerably.
 
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