From Shell itself.

Shell Rotella® T6 Full Synthetic oil features an advanced multi-functional, low-ash additive technology in a synthetic base oil designed to provide highly responsive protection that continuously adapts to your driving conditions. Use of selected low-viscosity synthetic base oils further energizes the oil’s protective capability that promotes fuel-economy performance with no compromise in durability. Shell Rotella® T6 can contribute in many ways:
• Extended-drain capable
• Energy saving – fuel-economy performance*
• Excellent engine cleanliness and wear protection
• Excellent extreme high/low-temperature protection
• Improved low-temperature flow*

http://www.shell.com/home/Framework?site.../t6_detail.html

Which makes perfect sense, given that Group III is considered full synthetic, and Shell's Group III base oil is a very fine product.

some claim it is unique because it is derived from severely hydrocracked slack wax or something along those lines, someone will correct me I'm sure. I like to think so but I'm a fan of it.

Johnnys' info on Pennzoil, Quaker State and Shell products is good info.

This is from the wildguzzi american street bike forums. Seems like someone from there "confirmed" through Shell also, that the Rotella T6 is infact from Group VI PAO based oils. Who knows what it is:

The stock for Rotella T6 HAS changed. It's now Group IV PAO. The thing I was most impressed with was the 33% wear reduction over the previous blend of Rotella 15w40 - which the BMW airhead riders, and old engine builders will swear by. I'm still not totally convinced the new Rotella is for me. I'm still waiting for a reply from Houston with the big Spectrochemical reveal.


In the world of "not really synthetic synthetics", the old formula of Rotella-T was fairly unique. Although Rotalla t's base stock was not PAO is wasn't Group III either. It was made from slack wax the same as Helix Ultra. Murphy confirmed through Shell that the new formula is now based on PAO for the Rotella T6 so this really is a different oil and I'm glad that, unlike some other mfgs, they didn't hide the change. I'll keep using the old stuff until folks like Murphy get a good look at this new "true syn".

Well, I was not going to post this, but here is the email communications starting at the bottom and working there way up. After reading it you can come to your own conclusions.

From: <shelltechnical-us@shell.com>
Date: December 21, 2009 10:11:37 AM CST
To: <jlp@charter.net>
Subject: Re: Shell Rotella T6

Johnny,
The T6 label is part of a marketing re-imaging of the Rotella line.
I don't believe there is much if any change otherwise for this
particular product.
Keith

On Mon, 21 Dec 2009 09:54:49 -0600 you wrote:

Keith,

Appreciate the reply, but it does not quite answer my question.

I've been to the Rotella.com site, looked at all the graphs, and
read
all of the information. And, we both agree it shows the Rotella T6
delivers 34% better wear protection that the previous CI-4 PLUS
formulation.
However, I have in my garage a case of gallons jugs of the Shell
Rotella T Synthetic 5W-40 that meets the CJ4 specification. I
purchased this oil from my Shell distributor about six or seven
months
ago. It's the same blue bottle as the new stuff, the difference is
the label on the gallon jugs. Mine do not say T6. So my question
is,
is the new T6 the same CJ4 product that I have now.

I am not a spy from one of your competitors. I am a retired Shell
employee and if that needs to be verified you can ask Dan A who I
am.

Thank you,

Johnny P


On Dec 21, 2009, at 7:40 AM, <shelltechnical-us@shell.com>
<shelltechnical-us@shell.com
wrote:

Johnny,
The new T6 formulation provides better wear protection and
low-temperature flow. See more at Rotella.com then select Products
then Select Rotella T6. You'll find a graph.
PROTECTION AGAINST WEAR
Shell Rotella® T6 delivers 34% better wear performance on average
compared to the previous API CI-4 PLUS 5W-40 formulation. In seven
out of seven industry-standard, diesel-engine wear test
measurements,
Shell Rotella® T6 outperformed the previous formulation.


Regards,
Keith
Shell Technical Information

On Mon, 21 Dec 2009 04:54:03 -0600 you wrote:

I see your comparisons to the older CI4+ Rotella T Synthetic
5W-40,
but how does it compare to the CJ4 Rotella T Synthetic 5W-40 that
the
new T6 replaced? What changed other than the label on the bottle?

Thank you,

Johnny P

Thanks Johnny for posting that. But it doesn't seem Shell technical really answered the question of whether its a Group III or Group IV, other than restate what is on the T6 label. In either sense, I it appears the T6 is a fine oil. I just switched over to the T6 from the Mobil 1 TDT in my '04 Ford 6.0 Powerstroke Diesel, and I will see how it holds up. Thanks again!

Reshard

Well, this quote tells me it's the same fine product that it was before.

Johnny,
The T6 label is part of a marketing re-imaging of the Rotella line.
I don't believe there is much if any change otherwise for this
particular product.
Keith

A major change in base stocks would be just that, a major change.

One of the few chemist I still know there did tell me they changed the viscosity index improver to make it more shear stable.

It has always been a great product and if I had a need for a diesel oil it is the one that I would use, no questions asked.

Awesome...thanks again!

Even if it is group III, Shells group III is perhaps the best group III base stick available. It's used to formulate the oil Ferrari uses has factory fill and in their Helix Ultra oils.

It's like Group III+.

The way I see it, if RTS now contained PAO, Shell would have surely tried to monetize on it by touting it in all its marketing materials, kind of like Castrol did when they started to sell Edge in the US, to make it look like something uber special and charge more money for it.

As Johnny's info confirms, it doesn't look like such formulation change has taken place. But again, we should not focus on whether it's Group III or IV, but rather on the actual price-to-performance aspects.

There are exceptions. For example, GC is believed to be a Group IV/V mix, and when on sale (which is quite often), it can be had for as little as $5/qt (same as Rotella T), and a free oil filter.

The fact that Ferrari use's a particular GIII base stock meanslittle to me. THink about what we have seen with the Good Doctors exotic fleet. They appear to be built like TOyota's with reguard to almost any synthetic oil even as far off from the recomended viscosity as the 0W20 and 5W20's that the good Doctor has used have produced great results. So Helix Ultra is just other over hyped and heavily marketed GIII. It does not matter to me how much a company hypes something a diamond is a diamond, a turd is a turd,POE is POE and GIII is GIII.......All of the above have purpose's and distinct chateristics no amount of hype or advertising will make any of them more then what they are and none of the above will go away anytime soon. None of the above can stand in for each other either. So if a GIII is all you need then so be it but lets leave the hype pf the magic pony out of oil!

Quatropete keep in mind that until about a year ago maybe 2 that RTS 5W40 sold for $12 a gallon so most of use that use it used to get it for $3 a quartnot on sale at it's full price. It has only been recently that my Walmart over the last year went from $12 to $16 then to $19 a gallon for RTS.

We also know that true GC had a mix of base stocks but was mostly PAO. It's magic was in it's high end European Gear Lube Viscosity Improver's. It has almost no additive package to speak of.....I think my well watter has more AW and EP additives then GC has.....LOL