The true meaning of "W"

[Volvo_ST1]

In this recent thread it is stated that the "W" in the engine oil grade designation, according to the SAE, does not stand for "winter" as commonly claimed by engine oil manufacturers.

Surely, the "W" does have a specific meaning, because a 0W and a 0 oil are not the same. For example, there are 20W-20 and 0W-0 oils.

Does anybody know for what the "W" really stands?

 

[Xstang]

This is a great video about the importance of W:
http://www.youtube.com/watch?v=Q7jDHL2Idwc

I apologize in advance.

Now, this link however:
http://www.sae.org/news/releases/rightoil.htm

While it doesn't outright say it, there is a VERY strong suggestion as to how an oll would perform while it was cold.

 

[Gene K]

Seeing as how Doctor Haas just did a drive by Im not sure if he misspoke or if he was actually told that.

I vaguely seem to recall having been told that the W at one time stood for something other than winter before. If so I imagine the SAE gave up on that decades ago.

 

[Volvo_ST1]

Originally Posted By: Xstang
This is a great video about the importance of W:
http://www.youtube.com/watch?v=Q7jDHL2Idwc

I apologize in advance.


As you should. We already know that the "W" has to do with low temperature performance. I only want to know for what the "W" stands, not what it describes.

 

[Volvo_ST1]

Originally Posted By: Gene K
Seeing as how Doctor Haas just did a drive by Im not sure if he misspoke or if he was actually told that.

I vaguely seem to recall having been told that the W at one time stood for something other than winter before. If so I imagine the SAE gave up on that decades ago.


Something a little more than hearsay or hazy memories would be nice.

Surely at least one of the professional tribologists that frequent the board knows the answer.

 

[pzev]

According to Valvoline, W stands for winter. If the SAE truly told Dr. Haas that W doesn't stand for winter, then surely they told him what it actually means, yet he didn't share this info. Did he mean to imply that it meant weight...as that was the topic of the thread, or was he simply bragging that he emailed the SAE and they replied back?

Anyways, link to Valvoline page where they state Winter is the definition. Look halfway down.

 

[Volvo_ST1]

pzev, did you read the last 12 words of the first sentence I posted in this thread?

This thread is about what the SAE says. I can't find anything.

 

[FowVay]

The "W" does represent the cold-flow standards of the fluid. It's odd to still be discussing this on this particular forum but the cold flow properties are measured completely different from the hot flow properties and the performance standards are completely different also.

A 20W-20 oil for example must meet the following standards:

20W = no more than 9500 centipoise (cP) measured at -15ºCelsius.
-20 = measure between 5.6 to 9.29 centistokes (cSt) at 100ºCelsius.

A normal monograde 20 will not meet the cold flow requirements and is therefore not categorized as a multi-grade. A 20W-20 is NOT just a different way of saying SAE 20.

Note that there is a difference between centipoise and centistoke and how the number is derived. That would be a nice discussion to help with the education on this board.

 

[BobFout]

0w mentioned here...

 

[Volvo_ST1]

Originally Posted By: FowVay
The "W" does represent the cold-flow standards of the fluid. It's odd to still be discussing this on this particular forum


What's odd is that my question is apparently difficult to understand. Can you grasp the difference between "For what does "W" stand and "What is the meaning of "W"? I didn't ask the second question. I even clarified, "I only want to know for what the "W" stands, not what it describes."

I want to literally know for what the "W" stands according to the SAE. That's my question and nothing else. If the SAE just picked a random letter it's fine.

 

[justinf89]

Well I've always thought winter.

 

[pzev]

Originally Posted By: Volvo_ST1
Originally Posted By: FowVay
The "W" does represent the cold-flow standards of the fluid. It's odd to still be discussing this on this particular forum


What's odd is that my question is apparently difficult to understand. Can you grasp the difference between "For what does "W" stand and "What is the meaning of "W"? I didn't ask the second question. I even clarified, "I only want to know for what the "W" stands, not what it describes."

I want to literally know for what the "W" stands according to the SAE. That's my question and nothing else. If the SAE just picked a random letter it's fine.



It means winter. Whatever the SAE intended it to mean is irrelevant when the vast majority of the industry defines it as Winter. It sounds like the SAE doesn't even really want to define it...so if the use of W is truly arbitrary, then they should have picked a better freaking letter lol, as its too [censored] confusing to the laymen.
Hence why it meaning winter makes the most sense to me...and apparently Valvoline.

 

[CarbonCrew]

The true meaning of 'W' is up for your interpretation. Officially SAE does not defines 'W' with only cold temperature cranking viscosities and only states the following:

"Two series of viscosity grades are defined in Table 1: (a) those containing the letter W and (b) those without the letter W.
Single viscosity-grade oils (“single-grades”) with the letter W are defined by maximum low-temperature cranking and
pumping viscosities, and a minimum kinematic viscosity at 100 °C. Single-grade oils without the letter W are based on a
set of minimum and maximum kinematic viscosities at 100 °C, and a minimum high-shear-rate viscosity at 150 °C. The
shear rate will depend on the test method used. Multiviscosity-grade oils (“multigrades”) are defined by both of the
following criteria"

API goes on to say that "The W rating of an oil is an indication of how fast your engine will turn over in Winter and how well the oil will flow to lubricate the critical parts."

Again, nothing definitive but definitely inferred. What you choose to believe is up to you.

 

[FowVay]

Originally Posted By: Volvo_ST1
Originally Posted By: FowVay
The "W" does represent the cold-flow standards of the fluid. It's odd to still be discussing this on this particular forum


What's odd is that my question is apparently difficult to understand. Can you grasp the difference between "For what does "W" stand and "What is the meaning of "W"?


Sorry to offend you.

 

[Volvo_ST1]

Originally Posted By: CarbonCrew
The true meaning of 'W' is up for your interpretation. Officially SAE does not defines 'W' with only cold temperature cranking viscosities and only states the following:

[snip]

"The W rating of an oil is an indication of how fast your engine will turn over in Winter [snip]"

Again, nothing definitive but definitely inferred. What you choose to believe is up to you.


Clearly, "W" stands for wabbit.

 

[Zaedock]

Bush Jr.

 

[d00df00d]

Volvo_ST1, I've been through this before. The only thing to do is to post another thread. I suggest something like the following:


"I know the W number indicates low temperature performance.

What I want to know is what WORD in the English language the W itself stands for.

Does anyone know?"

 

[Johnny]

Originally Posted By: Volvo_ST1
Originally Posted By: CarbonCrew
The true meaning of 'W' is up for your interpretation. Officially SAE does not defines 'W' with only cold temperature cranking viscosities and only states the following:

[snip]

"The W rating of an oil is an indication of how fast your engine will turn over in Winter [snip]"

Again, nothing definitive but definitely inferred. What you choose to believe is up to you.


Clearly, "W" stands for wabbit.


If wabbit was good enough for Elmer Fudd, it's good enough for me. Wabbit it is.

 

[eljefino]

If you want to know first hand what the SAE says about something, you have to pay. A lot.

You won't find it online for free.

If you are a lucky sort, your library will have some sort of subscription service that will let you in.

 

[Volvo_ST1]

Originally Posted By: eljefino
If you want to know first hand what the SAE says about something, you have to pay. A lot.

You won't find it online for free.





I don't need to hear it straight from the horse's mouth. Free, secondhand info is fine.

I find it hard to believe that it's a big secret that "W" stands for wabbit. On the other hand, it's possible that those people who do know really don't want to share their knowledge (for free or at all). That in turn makes me question all sorts of info that is liberally dispensed.