So... Is high viscosity index good or bad?

[Jimmy_Russells]

From the research I've been doing, it seems higher VI is typically the result of thinner base stocks using more VII's to spread out the viscosity a bit.

I have a 2018 Audi RS3 which is coming due for it's second oil change. The most economical oil in Canada in the 504 spec, by far, is Pennzoil Euro LX (Shell Helix Ultra ECT) 0W30. Looking at the specs, it is far thinner than most other 504 oils at 40°C and the viscosity index is much higher (204). The other oil I am considering is Total Ineo LongLife 5w30 which even at wholesale price is about 30% more expensive. I believe the Total is mainly group III and the Pennzoil mainly GTL.

From what I understand with the higher VI it is likely the Shell/Pennzoil will shear down a bit more and also probably has higher noack...?

Both being 504 approved oils it may not make much difference...?

 

[buster]

Depends on how you look at it. I prefer LESS VII's. Oils with a lot of VII's (lower quality base oils or large spread grades with poor quality VII's such as "some" 0w40's etc.) will lose their viscosity.

 

[ka9mnx]

I thought higher VI was an indication of better base stocks. For me higher VI is better.(?)

 

[BMWTurboDzl]

Depends upon the qualify of the VII's which I don't believe the layman can determine other than looking at used oil analysis. The reality is that the OE Oil Cert is designed to make this type of decision moot. In your case both are 504 so both should perform relatively the same.

 

[Mad_Hatter]

Originally Posted by Jimmy_Russells
From the research I've been doing, it seems higher VI is typically the result of thinner base stocks using more VII's to spread out the viscosity a bit.

From what I understand with the higher VI it is likely the Shell/Pennzoil will shear down a bit more and also probably has higher noack...?

Base stock(s) also contribute to the oils VI. Higher quality base stocks have naturally higher VI. Likewise, not a VM's are created equal. Some are low quality and shear easy(er) and some are of high quality and can withstand shear quite well. Seems to me that you would need to know the quality of the base oils and the type/quality of VM's to judge the oil with respect to VI.

 

[talest]

High and higher VI is a good thing.
Low and lower amounts of VIIs (different things) are less desirable.

VI = Viscosity Index
VII = Viscosity Index Improver

Sort of why 10w30 was preferred to 5w30 - and still may be - as to which one is more stable in-grade. Motor oil used to be a lot worse. And there is still indication 10W is better in heat than 5W, depends. As an example.

 

[sloinker]

It seems to me, and maybe I'm wrong, that oils with substantial IV/V base oils use less or no VII's at all. Naturally broad viscosity ranges and high shear tolerances without an additive that may not help and can hinder the function of the oil as intended.

 

[Mad_Hatter]

Originally Posted by BMWTurboDzl
Depends upon the qualify of the VII's which I don't believe the layman can determine other than looking at used oil analysis.

Can you take a used oil analysis showing the lubricants performance and ascribe it to either the viscosity modifier or base oil(s), without knowing anything about the quality, quantity & type of each?? (which is usually a trade secret)...Seems to me all it will show is how the end product performed (in that particular engine)???

 

[A_Harman]

The viscosity index for the Total oil is about average for quality synthetics, while the Shell oil has about the highest for a 30-weight that I can remember.
The flash point of the Total is 238C, and for the Shell is 226C. The higher FP of the Total may indicate lower NOACK volatility. But 226C is a very good FP.
It would be nice if Shell had provided the HTHS so that the Temporary Shear Ratio could be calculated.
If both meet the appropriate Audi spec, I say go for the Shell. It's lower cost to start with, and the higher VI may save a small amount of fuel, if your drive cycle has a lot of ambient starts and warmup time.

 

[Jimmy_Russells]

Originally Posted by A_Harman
The viscosity index for the Total oil is about average for quality synthetics, while the Shell oil has about the highest for a 30-weight that I can remember.
The flash point of the Total is 238C, and for the Shell is 226C. The higher FP of the Total may indicate lower NOACK volatility. But 226C is a very good FP.
It would be nice if Shell had provided the HTHS so that the Temporary Shear Ratio could be calculated.
If both meet the appropriate Audi spec, I say go for the Shell. It's lower cost to start with, and the higher VI may save a small amount of fuel, if your drive cycle has a lot of ambient starts and warmup time.


Do you need it exactly? Typically on these Euro oils they just say >3.5 and most seem actually in the 3.5 - 3.65 range.

I will probably go with the Pennzoil mainly because I don't mind spending some more money at all, but I want to know I'm actually getting something better for that money, like Ravenol VMP would be. Although at 2.5 - 3 times the price up here, that doesn't make any sense either. 50% more, sure.

Reading the Pennzoil site now however I'm wondering if this stuff is actually approved or not. The way I read it is the Fiat is recommended and the others are actual approvals, but they make it hard to tell:

 

[21Rouge]

Originally Posted by Jimmy_Russells
The most economical oil in Canada in the 504 spec, by far, is Pennzoil Euro LX (Shell Helix Ultra ECT) 0W30.


There is no doubt that this is an excellent oil and it can be got on sale for an excellent price.

But as you know from another thread I picked up a case of Mobil 1 ESP 0W30 (which has all the same certifications as the Pennzoil Platinum Euro) for a price of $11.30 per quart (including taxes)). It definitely does not have the VI of the above Pennzoil Platinum Euro but I have no doubt it is a superb oil. (I am currently using the same oil ie the M1, and have accumulated 5200 km on it. I will UOA it sometime later this Fall).

(Just curious why wouldn't you consider this new formulation of the Mobil 1 ESP 0W30 over the INEO Long Life 5W30?)

 

[demarpaint]

It depends on who you ask. I have read over the years here, more is better, and less is better. Based on that, which lead me nowhere, I say if the oil meets/exceeds the spec it's good to go.

 

[Jimmy_Russells]

Originally Posted by 21Rouge
Originally Posted by Jimmy_Russells
The most economical oil in Canada in the 504 spec, by far, is Pennzoil Euro LX (Shell Helix Ultra ECT) 0W30.


There is no doubt that this is an excellent oil and it can be got on sale for an excellent price.

But as you know from another thread I picked up a case of Mobil 1 ESP 0W30 (which has all the same certifications as the Pennzoil Platinum Euro) for a price of $11.30 per quart (including taxes)). It definitely does not have the VI of the above Pennzoil Platinum Euro but I have no doubt it is a superb oil. (I am currently using the same oil ie the M1, and have accumulated 5200 km on it. I will UOA it sometime later this Fall).

(Just curious why wouldn't you consider this new formulation of the Mobil 1 ESP 0W30 over the INEO Long Life 5W30?)


I would, but for how much?

The Pennzoil is $6.50 a litre at Canadian Tire on sale, which is at least once a month. That doesn't even include the $10 rebate. I can get the Total (or Motul 8100+ or Fuchs GT1) for about $8.50 per litre, or Liqui-Moly 4200 for about $10.50 per litre (I have a wholesale account from Germanparts.ca through work). Can the Mobil even touch this price?

 

[21Rouge]

Originally Posted by Jimmy_Russells
Originally Posted by 21Rouge
Originally Posted by Jimmy_Russells
The most economical oil in Canada in the 504 spec, by far, is Pennzoil Euro LX (Shell Helix Ultra ECT) 0W30.


There is no doubt that this is an excellent oil and it can be got on sale for an excellent price.

But as you know from another thread I picked up a case of Mobil 1 ESP 0W30 (which has all the same certifications as the Pennzoil Platinum Euro) for a price of $11.30 per quart (including taxes)). It definitely does not have the VI of the above Pennzoil Platinum Euro but I have no doubt it is a superb oil. (I am currently using the same oil ie the M1, and have accumulated 5200 km on it. I will UOA it sometime later this Fall).

(Just curious why wouldn't you consider this new formulation of the Mobil 1 ESP 0W30 over the INEO Long Life 5W30?)


I would, but for how much?

Can the Mobil even touch this price?


'Jimmy' as I wrote above I paid $11.30 per quart (including taxes).

 

[Jimmy_Russells]

Originally Posted by 21Rouge
Originally Posted by Jimmy_Russells
Originally Posted by 21Rouge
Originally Posted by Jimmy_Russells
The most economical oil in Canada in the 504 spec, by far, is Pennzoil Euro LX (Shell Helix Ultra ECT) 0W30.


There is no doubt that this is an excellent oil and it can be got on sale for an excellent price.

But as you know from another thread I picked up a case of Mobil 1 ESP 0W30 (which has all the same certifications as the Pennzoil Platinum Euro) for a price of $11.30 per quart (including taxes)). It definitely does not have the VI of the above Pennzoil Platinum Euro but I have no doubt it is a superb oil. (I am currently using the same oil ie the M1, and have accumulated 5200 km on it. I will UOA it sometime later this Fall).

(Just curious why wouldn't you consider this new formulation of the Mobil 1 ESP 0W30 over the INEO Long Life 5W30?)


I would, but for how much?

Can the Mobil even touch this price?


'Jimmy' as I wrote above I paid $11.30 per quart (including taxes).


Oh yeah ok I see that now. I have no doubt it is good stuff

 

[Rand]

To me the best answer would be: "Depends"

 

[Shannow]

If you re talking basestocks only, then higher VI is GREAT...but that maxes out at 130-140.
If you re talking finished oils, it depends.

Given that the "grade" is determined by the KV100, then previous commentary that thinner base oils and more VII are used is true...which can then be problematic in terms of viscosity retention with shear, and potential deposits.

GrIII with VIs to give over 200VI aren't my idea on a preferable oil design.

And the Japanese appear to agree with me, as their answer was 0W20 with stratospheric VI, which sheared down rapidly (CATERHAM's testing plus a couple of papers), which when they successfully lobbied to include 16 grade, they dropped the VI and VII treat rate considerably...Ravenol's 0W16 appears almost a monograde.

 

[JLTD]

Originally Posted by sloinker
It seems to me, and maybe I'm wrong, that oils with substantial IV/V base oils use less or no VII's at all. Naturally broad viscosity ranges and high shear tolerances without an additive that may not help and can hinder the function of the oil as intended.


True I believe...based on AMSOIL Signature Series 10w30, which was originally a straight 30 but meets the standards for 10w...

 

[JAG]

I agree with Rand and Shannow.

 

[OVERKILL]

Originally Posted by JAG
I agree with Rand and Shannow.


As do I.