Is VI an important factor when choosing a motor oil? Do higher VI numbers determine a motor oil to be better than lower VI numbered motor oils?
Viscosity Index
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Originally Posted By: Nate1979
Well lets see. Which manufacturer or any oil specifies a VI?
Let's use VML' numbers. The reason is, my nephew has a RMS leak on his 06 F150 4.2 V6. He chose to use VML 10W30. Yes, it specs 5W20, and 5W30 can be used just as well.
http://www.valvoline.com/pdf/maxlife_full_synthetic.pdf
Well lets see. Which manufacturer or any oil specifies a VI?
Let's use VML' numbers. The reason is, my nephew has a RMS leak on his 06 F150 4.2 V6. He chose to use VML 10W30. Yes, it specs 5W20, and 5W30 can be used just as well.
http://www.valvoline.com/pdf/maxlife_full_synthetic.pdf
Originally Posted By: Spooled
Valvoline does
Valvoline does what?
Valvoline does
Valvoline does what?
Originally Posted By: Spooled
Lists their VI numbers. Was replying to Nate's post.
Ah, ok. I was just a bit confused there.
I posted a link to those said numbers.
http://www.valvoline.com/pdf/maxlife_full_synthetic.pdf
Lists their VI numbers. Was replying to Nate's post.
Ah, ok. I was just a bit confused there.
I posted a link to those said numbers.
http://www.valvoline.com/pdf/maxlife_full_synthetic.pdf
No, Nate's post was regarding vehicle manufacturers and certifying bodies I believe.
Which vehicle manufacturers list a Viscosity Index in their oil selection guidelines ?
Which Oil certification body (ACEA or API) specify a viscosity index as part of a certification ?
Answer is nil.
Which vehicle manufacturers list a Viscosity Index in their oil selection guidelines ?
Which Oil certification body (ACEA or API) specify a viscosity index as part of a certification ?
Answer is nil.
5W3.4
(Not my idea, but Shannow's.)
5W, we know what that is.
3.4 is the HTHS
VI is somewhere in between.
Now ask yourself this question.
Is it really that cold outside that
necessitates 5W ?
If not, then why are you paying for it
when 10W or 15W will do?
At a given price point, something must
be lost for something gained.
What would you trade for 5W?
10W3.6 or 15W3.7?
(10W30 or 15W30 instead of 5W30)
For argument sake, they all cost the same.
Your only going to get what you pay for.
Pick one that fits your needs, whether
your needs are real or imagined.
(Not my idea, but Shannow's.)
5W, we know what that is.
3.4 is the HTHS
VI is somewhere in between.
Now ask yourself this question.
Is it really that cold outside that
necessitates 5W ?
If not, then why are you paying for it
when 10W or 15W will do?
At a given price point, something must
be lost for something gained.
What would you trade for 5W?
10W3.6 or 15W3.7?
(10W30 or 15W30 instead of 5W30)
For argument sake, they all cost the same.
Your only going to get what you pay for.
Pick one that fits your needs, whether
your needs are real or imagined.
Used_Oil,
Problem is that you can't (at least not here) get comparative similarity.
I'd get away with a 10W or 15W here any day of the year (25W70 still started the coldest days, and never took excessively long to send the OP light off).
But to get a synthetic (my choice, I don't "need" it(1)), I have to go to 5W or 0W...then if I do the HTHS thing, and try to have a sensible VI, I end up where I currently am, with 5W30 A3/B4...a 5W40 A3B4, with higher VI, usually higher KV40, more VIIs, and a thinner basestock makes little sense.
(1) which then has to have me question why I need synthetic, and the answer more than ever these days is probably not, and a 10W30 semisynth A3/B4 is 40% of the cost of M1 0W40.
Problem is that you can't (at least not here) get comparative similarity.
I'd get away with a 10W or 15W here any day of the year (25W70 still started the coldest days, and never took excessively long to send the OP light off).
But to get a synthetic (my choice, I don't "need" it(1)), I have to go to 5W or 0W...then if I do the HTHS thing, and try to have a sensible VI, I end up where I currently am, with 5W30 A3/B4...a 5W40 A3B4, with higher VI, usually higher KV40, more VIIs, and a thinner basestock makes little sense.
(1) which then has to have me question why I need synthetic, and the answer more than ever these days is probably not, and a 10W30 semisynth A3/B4 is 40% of the cost of M1 0W40.
My problem is that I agree with what you just said,
but can't figure out where I went wrong in my post.
With group II and II+ (XW20's and 16's) being so
close to group IIIs in performance,
(a synthetic for the purpose
of this discussion) why buy into the VI trap,
if as you imply, it's not always required?
Many areas of the USA and the west coast of Canada
have weather that would support the use of an engine
oil meeting no better than 20W.
After you posted the old M-1 blending chart, 0W40
fell off my favorites list, because, as you posted
above, it has a lower base oil viscosity (average)
and more VIIs than the 5W30 shown on the same chart.
And as a rule 0W40s cost more,
which was supposed to be my point,
but for some reason I came across wrong.
My ego isn't such that if you explained comparative
similarity I would be offended.
but can't figure out where I went wrong in my post.
With group II and II+ (XW20's and 16's) being so
close to group IIIs in performance,
(a synthetic for the purpose
of this discussion) why buy into the VI trap,
if as you imply, it's not always required?
Many areas of the USA and the west coast of Canada
have weather that would support the use of an engine
oil meeting no better than 20W.
After you posted the old M-1 blending chart, 0W40
fell off my favorites list, because, as you posted
above, it has a lower base oil viscosity (average)
and more VIIs than the 5W30 shown on the same chart.
And as a rule 0W40s cost more,
which was supposed to be my point,
but for some reason I came across wrong.
My ego isn't such that if you explained comparative
similarity I would be offended.
Last edited by a moderator:
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Originally Posted By: used_0il
My problem is that I agree with what you just said,
but can't figure out where I went wrong in my post.
With group II and II+ (XW20's and 16's) being so
close to group IIIs in performance,
(a synthetic for the purpose
of this discussion) why buy into the VI trap,
if as you imply, it's not always required?
I think you mean Group III and III+ vs PAO, no? Group II is certainly not "close" to synthetic in performance.....
Originally Posted By: used_0il
Many areas of the USA and the west coast of Canada
have weather that would support the use of an engine
oil meeting no better than 20W.
After you posted the old M-1 blending chart, 0W40
fell off my favorites list, because, as you posted
above, it has a lower base oil viscosity (average)
and more VIIs than the 5W30 shown on the same chart.
And as a rule 0W40s cost more,
which was supposed to be my point,
but for some reason I came across wrong.
Keep in mind that the chart is not showing you how to blend M1 0w-40, it is showing you how to blend a 0w-40 with those particular ingredients. Big difference and why the specs for that "example" 0w-40 don't look anything like M1 0w-40.
My problem is that I agree with what you just said,
but can't figure out where I went wrong in my post.
With group II and II+ (XW20's and 16's) being so
close to group IIIs in performance,
(a synthetic for the purpose
of this discussion) why buy into the VI trap,
if as you imply, it's not always required?
I think you mean Group III and III+ vs PAO, no? Group II is certainly not "close" to synthetic in performance.....
Originally Posted By: used_0il
Many areas of the USA and the west coast of Canada
have weather that would support the use of an engine
oil meeting no better than 20W.
After you posted the old M-1 blending chart, 0W40
fell off my favorites list, because, as you posted
above, it has a lower base oil viscosity (average)
and more VIIs than the 5W30 shown on the same chart.
And as a rule 0W40s cost more,
which was supposed to be my point,
but for some reason I came across wrong.
Keep in mind that the chart is not showing you how to blend M1 0w-40, it is showing you how to blend a 0w-40 with those particular ingredients. Big difference and why the specs for that "example" 0w-40 don't look anything like M1 0w-40.
I thought my music analogy was cute btw.
It was clear to him just from looking?
LOL...yeah.
Interesting brand, one add pack fits all (Penrite do similar)
http://media.supercheapauto.com.au/sca/files/user/content/chief-oils/tds/344491.pdf
http://media.supercheapauto.com.au/sca/files/user/content/chief-oils/tds/344493.pdf
Interesting brand, one add pack fits all (Penrite do similar)
http://media.supercheapauto.com.au/sca/files/user/content/chief-oils/tds/344491.pdf
http://media.supercheapauto.com.au/sca/files/user/content/chief-oils/tds/344493.pdf
It's too bad the HTHS is not listed for those
two engine oils.
My guess is that the HTHS of the 5W40 is not
proportionately higher than the 5W30 for the
KV100.
When SAE introduced the winter "W" designations,
the spacing was equal, moving up every 5C, except
for 20W and 25W, which has an approximate 4C
spacing. But instead, the viscosity allowance
was raised or given more headspace.
(Sorry, I couldn't resist the temptation.)
The SAE grades don't appear to follow an equal
scale of proportionate steps, and instead of
revising the list that would actually mean something,
they now have SAE 16.
Show me C Flat on a piano.
two engine oils.
My guess is that the HTHS of the 5W40 is not
proportionately higher than the 5W30 for the
KV100.
When SAE introduced the winter "W" designations,
the spacing was equal, moving up every 5C, except
for 20W and 25W, which has an approximate 4C
spacing. But instead, the viscosity allowance
was raised or given more headspace.
(Sorry, I couldn't resist the temptation.)
The SAE grades don't appear to follow an equal
scale of proportionate steps, and instead of
revising the list that would actually mean something,
they now have SAE 16.
Show me C Flat on a piano.
Originally Posted By: used_0il
It's too bad the HTHS is not listed for those
two engine oils.
My guess is that the HTHS of the 5W40 is not
proportionately higher than the 5W30 for the
KV100.
The GrIII 5W40s I've got/had are usually 3.8, the 5W30s usually 3.6, so yep, you are right.
Look at the -30 CCS, and the flashpoints...the 5W40 is (probably) a lighter average basestock than the 5W30...much like the mobil table suggests.
Originally Posted By: used_0il
When SAE introduced the winter "W" designations,
the spacing was equal, moving up every 5C, except
for 20W and 25W, which has an approximate 4C
spacing. But instead, the viscosity allowance
was raised or given more headspace.
(Sorry, I couldn't resist the temptation.)
The SAE grades don't appear to follow an equal
scale of proportionate steps, and instead of
revising the list that would actually mean something,
they now have SAE 16.
Show me C Flat on a piano.
Only semi rational reason I've seen for the grades is this (still trying to find an original J300 to add to my data), but here's the alleged verbage.
http://www.jcmotors.com/images/understanding_motor_oil_viscosity.pdf
The article has holes in it in other areas, that's why I'm chasing old J300s. As an aside, VI was based on their best crude being 100, and worst being 0, clearly what was available at the time, but even the "0" had a viscosity index.
Quote:
To properly answer that question a bit of history is required. Motor oil is like every other fluid in that its viscosity varies with temperature and pressure. Since the temperature and pressure conditions under which most automobile engines operate are reasonably constrained the viscosity requirements for a motor oil can be quantified and standardized. In the United States, the organization that sets the standards for performance of motor oils is the Society of Automotive Engineers (SAE). In 1911 the SAE published the first version of their standard (SAE J300) for motor oil viscosity. The SAE wanted a system that reflected the suitability of an oil for use as an engine lubricant and was easy for the consumer to understand. Their initial specification defined five different numbered grades for motor oil (10, 20, 30, 40, and 50). The grades were based on flow rates measured at 210° F (100° C) as shown in the table to the left. Very shortly the original specification was updated to use a standard scientific unit of viscosity (cSt) instead of time. By 1926 there were six grades of oil defined (SAE 10 through SAE 60) specified by viscosities measured at two temperatures - 130° F (55° C) and 212° F (100°C). Over time further shortcomings in this system were identified and it has been amended numerous times. A major change was made in 1952 when the original set of grade designations was augmented with the addition of a set of winter (“W”) grade designations (10W, 15W, 20W, 25W, 30W) which were specified by viscosity measured at 0° F. This change was instituted to address problems with cold weather oil performance. Engineers and consumers alike had come to realize that the existing grade specification did not adequately describe the cold weather nature of existing motor oils. At freezing temperatures an oil meeting specification SAE 20 refined from aromatic black Gulf crude was much thicker than an SAE 20 refined from light amber Pennsylvania crude. Engineers began to measure this difference in behavior with a viscosity ratio metric called the Viscosity Index (VI). The Gulf crude based oils which had lower indices did not provide the same level of engine protection in winter conditions as Pennsylvania crude based oils which had higher indices. This led to the well deserved reputations for superior cold weather protection of brands such as Pennzoil and Quaker State. Now engine manufacturer’s began to specify “W” grades for winter use.
by assigning 10 second bands back in the day, on kinematic viscosity, they made 20 a ridiculously wide viscosity band, and the others were "narrowed up" due to them being the same band, over a vastly different mean.
Trying to fit the 16s and whatnot in, they've carried on the abomination.
Should be xW-HTHS.
It's too bad the HTHS is not listed for those
two engine oils.
My guess is that the HTHS of the 5W40 is not
proportionately higher than the 5W30 for the
KV100.
The GrIII 5W40s I've got/had are usually 3.8, the 5W30s usually 3.6, so yep, you are right.
Look at the -30 CCS, and the flashpoints...the 5W40 is (probably) a lighter average basestock than the 5W30...much like the mobil table suggests.
Originally Posted By: used_0il
When SAE introduced the winter "W" designations,
the spacing was equal, moving up every 5C, except
for 20W and 25W, which has an approximate 4C
spacing. But instead, the viscosity allowance
was raised or given more headspace.
(Sorry, I couldn't resist the temptation.)
The SAE grades don't appear to follow an equal
scale of proportionate steps, and instead of
revising the list that would actually mean something,
they now have SAE 16.
Show me C Flat on a piano.
Only semi rational reason I've seen for the grades is this (still trying to find an original J300 to add to my data), but here's the alleged verbage.
http://www.jcmotors.com/images/understanding_motor_oil_viscosity.pdf
The article has holes in it in other areas, that's why I'm chasing old J300s. As an aside, VI was based on their best crude being 100, and worst being 0, clearly what was available at the time, but even the "0" had a viscosity index.
Quote:
To properly answer that question a bit of history is required. Motor oil is like every other fluid in that its viscosity varies with temperature and pressure. Since the temperature and pressure conditions under which most automobile engines operate are reasonably constrained the viscosity requirements for a motor oil can be quantified and standardized. In the United States, the organization that sets the standards for performance of motor oils is the Society of Automotive Engineers (SAE). In 1911 the SAE published the first version of their standard (SAE J300) for motor oil viscosity. The SAE wanted a system that reflected the suitability of an oil for use as an engine lubricant and was easy for the consumer to understand. Their initial specification defined five different numbered grades for motor oil (10, 20, 30, 40, and 50). The grades were based on flow rates measured at 210° F (100° C) as shown in the table to the left. Very shortly the original specification was updated to use a standard scientific unit of viscosity (cSt) instead of time. By 1926 there were six grades of oil defined (SAE 10 through SAE 60) specified by viscosities measured at two temperatures - 130° F (55° C) and 212° F (100°C). Over time further shortcomings in this system were identified and it has been amended numerous times. A major change was made in 1952 when the original set of grade designations was augmented with the addition of a set of winter (“W”) grade designations (10W, 15W, 20W, 25W, 30W) which were specified by viscosity measured at 0° F. This change was instituted to address problems with cold weather oil performance. Engineers and consumers alike had come to realize that the existing grade specification did not adequately describe the cold weather nature of existing motor oils. At freezing temperatures an oil meeting specification SAE 20 refined from aromatic black Gulf crude was much thicker than an SAE 20 refined from light amber Pennsylvania crude. Engineers began to measure this difference in behavior with a viscosity ratio metric called the Viscosity Index (VI). The Gulf crude based oils which had lower indices did not provide the same level of engine protection in winter conditions as Pennsylvania crude based oils which had higher indices. This led to the well deserved reputations for superior cold weather protection of brands such as Pennzoil and Quaker State. Now engine manufacturer’s began to specify “W” grades for winter use.
by assigning 10 second bands back in the day, on kinematic viscosity, they made 20 a ridiculously wide viscosity band, and the others were "narrowed up" due to them being the same band, over a vastly different mean.
Trying to fit the 16s and whatnot in, they've carried on the abomination.
Should be xW-HTHS.
All I was curious about was the VI in the 10W30 (143) compared to the VI in the 5W30 (168). Being the VI is higher in the 5W30, does this mean it would be a better choice than the lower VI in the 10W30?
BTW, I asked my nephew to listen to his engine for any unusual noises upon start up and to let me know. He told me today that the engine is very quiet upon start up.
BTW, I asked my nephew to listen to his engine for any unusual noises upon start up and to let me know. He told me today that the engine is very quiet upon start up.
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