GP II, GP II+, GP III Question

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I found this on the Conoco site while looking for something else:

Quote:
Group III - Unconventional Base Oils

The API defines the difference between Group II and III base oils only in terms of V.I., viscosity index. Base oils with conventional V.I. (80-119) are Group II and base oils with an "unconventional" V.I. (120+) are Group III. Group III base oils are also called unconventional base oils (UCBO's) or very high V.I. (VHVI) base oils. Group II+ base oils have the same maximum V.I. as Group II (80-119), but have a higher minimum V.I. (110-119).

From a process standpoint, Group III oils are made by the same process as Group II oils, but the V.I. is increased by increasing the temperature of the hydrocracker. The product V.I. can also be increased by increasing the V.I. of the feedstock. Which is done by selecting the appropriate crude.



SURELY, there must be more/greater differences between II/II+ and III than VI. If not, and you have a compulsive/obsessive disorder, such as I have, and change your oil every 3000 miles, what is there to influence going to a gp III? Why wouldn't, for example only, say Pennzoil YB with a good VII add, which I assume it has, offer the same qualities as Pennzoil Platinum with a short OCI?
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Same thought process for Valvoline Premium vs Synpower, or whoever else.

I assume I am missing something really important here.
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Does increasing the temperature of the hydro-cracker also create a "purer" base oil? Does this mean the molecules of a gp III are more uniform that the molecules of a gp II+? ON the other hand, if gp III is just a higher VI gp II, why not go from gp II to gp IV if I were going to synthetic, given the small difference in price between III and IV?

Your knowledge greatly appdreciated.
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Group III and Group II both have to have >90% saturates (isoparaffins). If a base oil has >90% saturates and a VI of >120, it's Group III. If the VI is <120, it's a Group II.
 
Originally Posted By: FrankN4
Does increasing the temperature of the hydro-cracker also create a "purer" base oil? Does this mean the molecules of a gp III are more uniform that the molecules of a gp II+?

AFAIK, it's basically that plus some other improvements.

Keep in mind that not all Group III base stocks are made by the same methods any more. There are new processes, like GTL, that produce even better base stocks.

However, the idea is the same.


Originally Posted By: FrankN4
ON the other hand, if gp III is just a higher VI gp II, why not go from gp II to gp IV if I were going to synthetic, given the small difference in price between III and IV?

PAO isn't all better than Group III. It has a lot of big advantages, but also less film strength and a few other disadvantages. You really only need PAO in certain applications, especially given how good Group III base stocks are getting nowadays.
 
But the process of further hydro cracking it, changes the nature of the oil, and how it acts, according to VI, uniformity of molecules, lesser contaminates that effect how the oil acts over time etc etc. Give it those further characteristics to match the PAO oils in certain aspects.

I personally prefer Group 3 in my engine, as its all i need, as the above has mentioned, and performs better in the areas that benefit me. Its advantage is that it is so close to the mineral oils my car has always been run on.
 
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I figure with my stock 2008 Hyundai Accent at a whopping 1.6 liters, which rages at 7000 RPM and produces 110HP and maybe 160 Lb/Ft torque at around 5000 RPM, but rarely sees even 3000 RPM, I could use Wesson Soy-based vegetable oil and do 200K with no problem. I believe my mower makes more horsepower at full speed than my car's engine just tooling around.

Therefore, I pick the oil that's CHEAP! And frankly, so could most of the rest of YOU!
 
"Therefore, I pick the oil that's CHEAP! And frankly, so could most of the rest of YOU! "

Well, it's always good to have someone around with that perspective. But it doesn't help your cause that you don't know that 160ft/lb at 5000 rpm would be 152 hp at that same rpm, which contradicts a hp quote you made in the exact same sentence. If you don't know that about how engines work, what else are you missing?

Many times group III's are so cheap, in the $15.00 for 5qts, the advantages of it are worth it wherever it came from. 40 points difference in VI for less than five bucks, plus whatever additive difference there is. In Mobil for example, there is significantly more detergent in the M1 than the clean 5000.

"Mobil Clean 7500 is a synthetic blend formulation with a boosted level of cleaning performance, 18 percent beyond the level of even our premium Mobil Clean 5000 conventional motor oil, to keep your engine cleaner longer." - mobiloil.com
 
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The best thought would be do you realistically need the improved basestock? Especially considering engines, barring mechanical failure which any basestock oil will not help or prevent,will outlast your ownership of the vehicle. So unless you realistically run the engine hard enough to need a higher base stock or live in a cold enough area to realistically benefit from a higher basestock. Or to realistically extend you oil change intervals where an increase in basestock and add package will help . GPII and GPII+ will get the job done and then some.
 
I read this post yesterday and last night it registered. I think there must be a connection between viscosity, ht/hs viscosity and viscosity index in pcmo.

"Group II+ base oils have the same maximum V.I. as Group II (80-119), but have a higher minimum V.I. (110-119)."

Is there any chance Chevron Supreme and Havoline DS are ALWAYS made with ONLY group II+ base stock since Chevron is the producer?
 
Originally Posted By: bepperb
"Therefore, I pick the oil that's CHEAP! And frankly, so could most of the rest of YOU! "

Well, it's always good to have someone around with that perspective. But it doesn't help your cause that you don't know that 160ft/lb at 5000 rpm would be 152 hp at that same rpm, which contradicts a hp quote you made in the exact same sentence. If you don't know that about how engines work, what else are you missing?


Well, aren't YOU the haughty one, Bepps? Excuse for the typo. 106 on the torque rating, not 160. Meanwhile, it doesn't change a thing as to what I said. DOHC family cars without turbos using SM/GF4 rated oils in Dino are just as good out to 5000 miles as any synthetic. Me, I'm not missing a thing. These oils, dino or synthetic, have the same effect and benefit unless you're going long, long drain, or are in some ultra low or high temperature extreme. And that simply isn't 95% of the motoring public. The rest of the car will wear out and rot long before your engine gets worn out to where it burns even one drop of oil during an OCI. And that's on dino, quite apart from synthetic. Please. You can tell yourself it matters, but it doesn't justify the cost to run these synthetics at these prices at the OCI most of the folks here are running. Not under SM/GF4. And THAT, Bepps, is what YOU are missing.
 
Originally Posted By: jorton
I read this post yesterday and last night it registered. I think there must be a connection between viscosity, ht/hs viscosity and viscosity index in pcmo.

"Group II+ base oils have the same maximum V.I. as Group II (80-119), but have a higher minimum V.I. (110-119)."

Is there any chance Chevron Supreme and Havoline DS are ALWAYS made with ONLY group II+ base stock since Chevron is the producer?


I think Chevron's IsoSyn is a trademark for its Grp II+ base stock.
 
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