Of 0w-20 oils, which have highest VI

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Bet this has been asked in the past, but with the motor oil formulation changes I thought it might be a start to see what is out there.

TGMO 0w-20 has a VI of 227 (2018)
 
That's some healthy VI in such a low multi-grade oil. Wonder how they achieved that.
And yeah, higher the better = More resistant to viscosity change.
 
Originally Posted by js1956
That's some healthy VI in such a low multi-grade oil. Wonder how they achieved that.
And yeah, higher the better = More resistant to viscosity change.

not necessarily so.
 
Originally Posted by CT8
Originally Posted by js1956
That's some healthy VI in such a low multi-grade oil. Wonder how they achieved that.
And yeah, higher the better = More resistant to viscosity change.

not necessarily so.


Right. I still can't find clear answers about lubricity and stability of VII additives. Gokhan goes into much detail about calculated HTFS (severe lubrication) capability, which seems to discount VII additive. (e.g., VII additive does nothing, really)

Reminds of the old Detroit 2-stroke smokers running straight weigh 40's & 30's to keep the rod slipper bushings from failing from too low viscosity. Or the original PAO's with "naturally high VI". So much fog factor marketing now.
 
Originally Posted by CT8
Originally Posted by js1956
That's some healthy VI in such a low multi-grade oil. Wonder how they achieved that.
And yeah, higher the better = More resistant to viscosity change.
not necessarily so.


True.
Also viscosity has nothing to do with how well it protects engine against wear like some people maybe think. That's where additives come to play.

One needs to also look at cSt @ 104°F and cSt @ 212°F and calculate how much reduction in viscosity there is between those two temps.

Yeah, there's lot more to oil than just a VI number.
 
VI isn't a parameter I really care much for. I also don't follow the mantra that all VII is bad as some VIIs are very shear stable.

A higher VI is not synonymous with a superior base oil. In fact, it can mean exactly the opposite in some applications. I look at the CCS, KV100, NOACK, and HTHS. The actual composition of the oil is equally as important. An oil that's all homopolymer PAO can have a very VI, but make a terrible engine oil.
 
Originally Posted by RDY4WAR
VI isn't a parameter I really care much for. I also don't follow the mantra that all VII is bad as some VIIs are very shear stable.

A higher VI is not synonymous with a superior base oil. In fact, it can mean exactly the opposite in some applications. I look at the CCS, KV100, NOACK, and HTHS. The actual composition of the oil is equally as important. An oil that's all homopolymer PAO can have a very VI, but make a terrible engine oil.


Where to find HTHS data? A number of lube vendors are limiting access to data sheets now. They are only required by law to provide a safety data sheet.
 
HTHS data is the most important data point in my buying decisions. Most companies don't publish this data and they are crossed off my "to buy" list. Seems Mobil1 has recently gone this route too. I was very disappointed when PQIA dropped HTHS from their reports several years ago.
 
Originally Posted by ka9mnx
HTHS data is the most important data point in my buying decisions. Most companies don't publish this data and they are crossed off my "to buy" list. Seems Mobil1 has recently gone this route too. I was very disappointed when PQIA dropped HTHS from their reports several years ago.

Go by grade then, or approvals. You know what the minimum HTHS is of a Mercedes-Benz 229.5 oil is for example, or an A3/B4 oil. That's why approvals and specifications are more important than PDS. I wouldn't "cross off" an oil that has an approval which dictates a specific HTHS.
 
Well I agree on that. My old vehicles don't have approvals or outdated approvals. Spec oil for the F150 and 4Runner are no longer available (SG and SH) so I guess I'm not running approved oils in those vehicles.
I do go by grade though and the F150 likes the proper grade with HTHS nearing the upper limit (ACEA A3). Fuel economy oils tend to stay towards the lower HTHS limits. I've given up on chasing oil for my vehicles and use the grade, PDS and price for my decisions. I don't think it really matters in my case.
 
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