Will the real base oil please stand up!

[TallPaul]

quote:

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Originally posted by Jay:
There is no base oil info available, or even implied, in the SAE multi-viscosity designation. Furthermore, there is no such thing as 0-weight, 5-weight, 10-weight, or 15-weight motor oil. These are all valid "w" (winter) designations, however.

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Here are the actual listed grades from the tech data sheet on Valvoline All-Fleet Plus Engine Oil:

15w40
10w30
10w
20w
30
40
50

Of course the multi-viscosity designation does not give or imply anything about the base oil. However, it seems a pretty safe assumption that the base oil viscosity would fall somewhere in the same range as the multi-viscosity designation.

While the Redline info is probably dated (or grossly oversimplified), it made more sense to me than to say the "w" number is approximately the base oil (that idea pops up all too often). I knew an oil company was not going to get a 20-weight base oil (they don't come that way) to build their multigrade, but would use a base oil that, under the API grades, would be a 20-weight (though apparently from the above information it could be thinner than that, or thicker).

What I did not realize, but MolaKule stated, was that they use two or more different viscosity base oils blended together to get the final base oil for a particular multigrade or straight weight oil. Even so, the final base oil blend they come up with will fit the viscosity range of one of the API grades, and on a 20w50 I doubt that grade would be either 20 or 50 for a conventional oil (though the viscosities blended to get the final base oil may well go outside this range).

 

[Jay]

Gary, TallPaul, in the case of single SAE designations such as 10w and 20w, the manufacturer is saying that the oil meets the 10w or 20w winter designation only. No hot-temperature tests are specified.

I can't find the spec for the Delo 10w, but the kinematic viscosity of Valvoline 10w @100C is in the 20-weight range.

A straight 20-weight oil would say "20" on the bottle. A bottle meeting the cold temperature designation of 20w (only) would say "20w" and may or may not be 20-weight.

quote:

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However, it seems a pretty safe assumption that the base oil viscosity would fall somewhere in the same range as the multi-viscosity designation.

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Why is that a safe assumption? If what you say is true, please tell me the range of viscosity of 0- weight engine oil, 5-weight?, 10-weight?, 15-weight?

(Hint: There's no such thing.

)

 

[Gary Allan]

quote:

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A straight 20-weight oil would say "20" on the bottle. A bottle meeting the cold temperature designation of 20w (only) would say "20w" and may or may not be 20-weight.

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First ..this begs the question, Why call it a 20W if in fact it has no relavence to the indicated weight??


So you're saying that a "10W" is actually a 10W-20??

If you will can you define the current "W" designation criteria? This should be totally independant (at least it used to be back in the grandpappy Group I days - probably before it was called Group I) of the weight designation. That is, don't all oils, regardless of their designation, have to pass the same test for the "W" to be affixed ..as in a minimum??? Isn't this standard "fixed"? Otherwise ..every weight would have a "W" indexed for their respective weight

Can you get a grip on my

 

[TallPaul]

quote:

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Originally posted by Jay:
...If what you say is true, please tell me the range of viscosity of 0- weight engine oil, 5-weight?, 10-weight?, 15-weight?

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There are no weights 0, 5, 10, and 15. There are, however, classifications of 0w, 5w, 10w, and 15w. Each of these must meet a minimum 100C viscosity. Therefore, I am saying for example, that it is pretty safe to assume that a 5w30 will have a base oil with a 100C viscosity between 3.8 (the min for a 5w oil) and less than 12.5 (the upper limit of a 30-weight oil).

 

[Gary Allan]

Jay ... now I'm certainly happy to provide the entertainment here

..but you're leaving out a few key elements that put this thing together (visions of some good old boy having fun with the "greenhorns" out in the woods).


Okay ..it would make sense, given the narrow range that 10 weight would exist in ..that a given oil is yet to be developed that could be stable enough to remain within the confines of the 10 weight designation. This kinda negates anything being labeled 10 "W". Why isn't called 5W-10 or 0W-10, 5w-20 or 0w-20? (yes, there are some of these oils some new ..some not..but why call anyting 10W)?

Now somehow ..I can see you spinning this around on the other end of scale ...at which time we'll be right back to where I started with the assertion that a 10w30 is really a 20 weight oil (visions of "You can't just say the cat died").

Okay ..I'm ready to take one step to the left after I've just been led on a 4 mile obstacle course ending up at the starting line

 

[Jay]

First ..this begs the question, Why call it a 20W if in fact it has no relavence to the indicated weight??

This is a good question, but, in fact, it does have no relevence to the hot-temperature designation. I think the SAE could have side-stepped a mountain of confusion if they had given the winter designation a single letter such as "A" or "B","C", etc. C-30 oil would end a lot of misconceptions about what the multi-viscosity designation means.

So you're saying that a "10W" is actually a 10W-20??

No, I'm saying that that particular Valvoline oil's viscosity at 100C falls in the 20-weight range (from reading the spec sheet). A 10W oil meets the two cold-temperature requirements of 10w (say "double-u" not "weight"). We don't know what the hot-temperature "weight" or grade of the oil is from it's SAE designation.

If you will can you define the current "W" designation criteria?...

Here's an SAE J300 chart on page 3. It takes a little study to understand, but it has all the cold and hot temperature requirements.

 

[Jay]

quote:

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Originally posted by TallPaul:

quote:

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Originally posted by Jay:
...If what you say is true, please tell me the range of viscosity of 0- weight engine oil, 5-weight?, 10-weight?, 15-weight?

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There are no weights 0, 5, 10, and 15. There are, however, classifications of 0w, 5w, 10w, and 15w. Each of these must meet a minimum 100C viscosity. Therefore, I am saying for example, that it is pretty safe to assume that a 5w30 will have a base oil with a 100C viscosity between 3.8 (the min for a 5w oil) and less than 12.5 (the upper limit of a 30-weight oil).

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OK. I'm not a blender, so I don't know. I do know that some of M1's supersyn basestocks are well over 100cSt @ 100C which kind-of shoots holes in that theory.

 

[Jay]

..but why call anyting 10W?...

I'd be interested to know this myself. What engine requires 10w oil, and why? In an arctic environment I would much rather have a 0w-20, and, in fact, 0w-20 is one of the oils Caterpillar recommends for some of it's engines in really cold environments.

As to the rest of your post, just keep in mind that the numerical term of the SAE low-temperature multi-viscosity designation has a completely different meaning than the high-temperature multi-vis designation.

 

[Gary Allan]

I can't for the life of me format this right

btw- thank you for the help for the "challenged"

b-btw-I somehow found what I was looking for on page 2- you're right ..I had difficulty integrating some of these charts without adaquate indexing for worth (boucing it off someone to get "in").

Okay ..this basically reinforces my assertion that the "W" is a "static spec" ..a finish line. The numerical assignation is mere an indication of the performance at that spec. That is, any oil that evidences "no stress" can have a "W" affixed to it.

SAE Low Temperature (°C) Low Temperature (°C) Kinematic Kinematic High-Shear
Viscosity Cranking Viscosity(1), Pumping Viscosity(2), cP Max. Viscosity(3) (cSt) Viscosity(3) (cSt) Viscosity(4) (cP) at 150°C
Grade cP Max. with No Yield Stress at 100°C Min. at 100°C Max. and 106 s-1 Min.
0W 6200 at -35 60 000 at -40 3.8 - -
5W 6600 at -30 60 000 at -35 3.8 - -
10W 7000 at -25 60 000 at -30 4.1 - -
15W 7000 at -20 60 000 at -25 5.6 - -
20W 9500 at -15 60 000 at -20 5.6 - -
25W 13000 at -10 60 000 at -15 9.3 - -
20 - - 5.6 less than 9.3 2.6
30 - - 9.3 less than 12.5 2.9
40 - - 12.5 less than 16.3 2.9 (0W-40, 5W-40,
and 10W-40 grades)
40 - - 12.5 less than 16.3 3.7 (15W-40, 20W-40,
25W-40, 40 grades)
50 - - 16.3 less than 21.9 3.7
60 - - 21.9 less than 26.1 3.7
All values are critical specifications as defined by ASTM D 3244.
1 cP=1 mPa.s; 1 cSt=1 mm2s-1
Notes:
(1) ASTM D 5293.
(2) ASTM D 4684. Note that the presence of any yield stress detectable by this method constitutes a failure regardless of viscosity.
(3) ASTM D 445.
(4) ASTM D 4683, CEC L-36-A-90 (ASTM D 4741), or ASTM D 5481.

I admit that it would be rather confusing to see a 10W-0, 25w-10, or 15w-10 oil on the shelf.

So now ..and I think we're dealing with "flukes" in practical nomenclature ...

In a multivisc, when we see a 10w30, are we looking at an oil that meets the 100 C requirements of 30 weight oil ...has NO resemblence to a 10 weight @ 40 C ..but evidences the appropriate "no stress" @ -25? ..OR..are we looking at an oil that meets the 100 C spec to qualify for a 30 weight, meets the 40 C spec for 10 weight ..and we don't have a clue of where it sits in the "no stress" test??

We're close to the lighbulb going off here (yes, the "release" is close folks)

[ September 06, 2004, 03:06 PM: Message edited by: Gary Allan ]

 

[TallPaul]

quote:

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Originally posted by Jay:
I do know that some of M1's supersyn basestocks are well over 100cSt @ 100C which kind-of shoots holes in that theory.

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I realize the base oils blended into a particular mix have widely varying viscosities, some outside the multigrade range, but I am talking about the completed mixture's final viscosity being within that range, and I believe I am right.

quote:

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Originally posted by Jay:
A 10W oil meets the two cold-temperature requirements of 10w (say "double-u" not "weight"). We don't know what the hot-temperature "weight" or grade of the oil is from it's SAE designation.

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We do know that the hot temp (100C) viscosity of a 10w (double-u) must be at least 4.1 because that is how the SAE chart defines it.

 

[Jay]

quote:

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Originally posted by Gary Allan:

In a multivisc, when we see a 10w30, are we looking at an oil that meets the 100 C requirements of 30 weight oil ...has NO resemblence to a 10 weight @ 40 C ..but evidences the appropriate "no stress" @ -25? ..OR..are we looking at an oil that meets the 100 C spec to qualify for a 30 weight, meets the 40 C spec for 10 weight ..and we don't have a clue of where it sits in the "no stress" test??

We're close to the lighbulb going off here (yes, the "release" is close folks)

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The former, I think.

Gary, as you know, motor oil viscosity varies with temperature. They all get thinner as they warm and thicker as they cool. Since viscosity varies with temperature, how do you tell someone what weight or grade a motor oil is? The SAE does this by specifying kinematic viscosity at one fixed temperature--100degC (and then specifying a minimum HTHS viscosity along with it). That's what the number designation on the right is. I think you understand this.

The number on the left has nothing to do with 40 deg C, 0 deg C, or any other temperature except the ones shown on the chart. Using your 10w30 example and looking at the J300 chart, the oil is 30-weight because it's kinematic viscosity @ 100C is between 9.3 and 12.5cSt and it's HTHS is greater than 2.9cP. So much for the hot-temp stuff.

In addition, it has a cranking viscosity less than 7000cP @ -25C and a pumping viscosity less than 60000cP @-30C (with no yield stress). That's all the 10w means--nothing more.

Test your knowledge:

1. Could the 10w30 oil be classified as 10w?
2. What about 15w? 20w? 25w?
3. Could the 10w30 be classified as 30 (straight 30-weight)?
4. Could it be classified 25w30?

The answers are on the SAE J300 chart.

[ September 06, 2004, 07:17 PM: Message edited by: Jay ]

 

[Jay]

TallPaul, agreed.

 

[Gary Allan]

Thank you!

 

[Jay]

I reread this thread more carefully and realize that I misunderstood what you were saying from the beginning. The Redline FAQ got me so angry.

I'll be quiet now.

 

[TallPaul]

Putting my newfound knowledge into practice (I now know just about enough to be dangerous

) I created either a thicker 10w40 or a thin 15w40. Here's what I did. Just filled crankcase with Citgo Superguard 10w40 and noticed oil pressure was about 3 psi lower than with Maxlife 10w40 and Durablend 15w40. While I realize this is not a problem, I had gotten used to seeing a particular reading on the gauge. So I added 15 oz of straight 40 weight conventional to the Citgo 10w40 and volia!--Oil pressure up 3 psi. Basically I just boosted the high side of the base oil and spread the VIIs a little thinner to compensate, right? Seems better than adding pure VII to get higher viscosity.

So now if I can get the formula right I can make my own PCMO 15w40s, filling a gap in the market (the market of me, because apparently nobody else cares if there is PCMO 15w40).

I know I really should not mess with these high tech oils that had so much research put into them, but I can't help myself--

Oh yeah, not to do this in winter as the cold properties probably suffer.

 

[Jimbo]

quote:

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Originally posted by Jay:


I can't find the spec for the Delo 10w, but the kinematic viscosity of Valvoline 10w @100C is in the 20-weight range.

A straight 20-weight oil would say "20" on the bottle. A bottle meeting the cold temperature designation of 20w (only) would say "20w" and may or may not be 20-weight.

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I know Im a little late to this discussion, but here is the data for Delo 400 single grades in question.

10W has a cSt at 100C of 7.9 and a Cold Crank Poise of 31.5 at -20C.

20 is not listed as a 20W nor 20W-20. cSt at 100C is 8.9. There is no Cold Crank listed since there is no W designation.

[ September 07, 2004, 06:14 PM: Message edited by: Jimbo ]

 

[MolaKule]

quote:

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Why call it a 20W if in fact it has no relavence to the indicated weight??

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The "W" does not denote weight "grade." It signifies equivalent viscosity characteristics for a 20 weight at winter test temperatures.

What it signifies is that this oil performs as would as a straight 20 weight viscosity oil at the temperatures specified for "winter" (cold temperature) testing.

A 20W50 for example, has 20 weight viscosity oil characteristics for cold temperatures, and has 50 weight viscosity characteristics at 100 C. A 20W50 will have a 100 C spec of about 18 cSt or so.

For mineral oils, this is done primarily by the mix of base oil viscosities and VII's; for full synthetics, this is accomplished primarily by careful selection of various base viscosities alone. For multigrades, the closer the two numbers, the less chance VII's will be needed.

 

[Gary Allan]

quote:

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The "W" does not denote weight "grade."

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I'm that far ..I always have been. Now the number associated with it is merely a "performance rating" as THIS oil performed in the FIXED "W" test. This is "news".

 

[XS650]

quote:

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Originally posted by Jay:
If what you say is true, please tell me the range of viscosity of 0- weight engine oil, 5-weight?, 10-weight?, 15-weight?

(Hint: There's no such thing.

)

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I agree as far as J300 goes, but to sidetrack your thread slightly... do you know where the standards for shock absorber oils rated 5, 7.5, 10 weight and other thin numbers come from? I've never been able to find an SAE ref.

 

[XS650]

quote:

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Originally posted by Gary Allan:

quote:

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The "W" does not denote weight "grade."

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I'm that far ..I always have been.

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Not always. 40 years ago it refered to the viscosity at 0F.