Oil is NOT thinner when cold.

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Why do people still think that a 5w30 is a 5 weight when cold?

No oil is thinner when cold.

People on another board are trying to tell me that a 5w30 is a 5 weight when cold and a 10w30 is a 10 weight when cold.

So a 0w30 must then vanish when cold................
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Feel better now?
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It's funny how different folks need this explained in different ways to "get it". Some people need it explained multiple ways and multiple times. Sadly, I think some people never get it, and I include some motor press and mechanics in that group.
 
quote:

Originally posted by BlazerLT:
People on another board are trying to tell me that a 5w30 is a 5 weight when cold and a 10w30 is a 10 weight when cold.

Well...there is a kernal of truth in what they are saying. A 5w30 is going to have the cold flow properties of a 5w oil at "cold" temps (-30 by the SAE J300 specs) and will have the high temp flow properties of a 30 weight at "hot" temps (+100 by the SAE J300 specs). So what you have is an oil that acts like a 5w for cold starts and acts like a 30 weight at operating temp.
 
quote:

Originally posted by G-Man II:

quote:

Originally posted by BlazerLT:
People on another board are trying to tell me that a 5w30 is a 5 weight when cold and a 10w30 is a 10 weight when cold.

Well...there is a kernal of truth in what they are saying. A 5w30 is going to have the cold flow properties of a 5w oil at "cold" temps (-30 by the SAE J300 specs) and will have the high temp flow properties of a 30 weight at "hot" temps (+100 by the SAE J300 specs). So what you have is an oil that acts like a 5w for cold starts and acts like a 30 weight at operating temp.


How can a 5w30 have the flow characteristics of a 5 weight at -30 when it is thicker than molassis (sp?).
 
Well, I think what G-Man is referring to is that a 5W oil (read 5 dub ya) has the property of max 6600 cP at -30C.

Reading 5W as 5 weight doesn't make sense, as a SAE 5 viscosity grade does not exist.

I agree with Blazer that this "thin when cold, thick when hot" analogy shows up waaay to often!
 
quote:

Originally posted by BlazerLT:
How can a 5w30 have the flow characteristics of a 5 weight at -30 when it is thicker than molassis (sp?).

Because a 5w oil IS "thicker than molassis" at -30. It's just thinner than a 10w would be at that temp, and MUCH thinner than a 30wt would be (since a 30wt would be solid).

If you're operating under the assumption that a straight 5w oil is "water thin" at sub zero temps, you are sadly mistaken. ALL oils are extremely viscous at cold temps, especially when you get bellow zero. The grades such as 0w and 5w are just "less thick" than 10w, 15w, and 20w.
 
After following the link to the Neon forum, I see the Neon guys are linking back this Bitog thread.
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So here's my definition:

A multi-viscosity oil is less thick than the equivalent straight grade at very cold temperatures.

The W designation in a multi-viscosity oil grade stands for Winter and is the cold temp flow measured in centipoise, at a specific sub-zero temperature.

A 0W is 6200 max cP at -35C
5W is 6600 max cP at -30C
10W is 7000 max cP at -25C

A SAE "10 weight" or "5 weight" category does not exist.

The statement "A 5W-30 flows like a 5W oil at -30C(-22F)" is true since both 5W-30 and 5W have the same 6600 max cP @ -30C limit. Do not read 5W as a 5 weight oil - it is 5 "dub ya" and indicates a cold temp flow limit.

The SAE J300 Viscosity Chart
 
quote:

Originally posted by Nick29:
btw, trex, according to one of AE Haas's articles, dino oils begin as the lower number and have viscosity modifiers added to make them behave like the higher number and synthetics begin at the higher number and have modifiers to make it act like the lower number.

No disrespect to Dr Haas, but if that's what he wrote about synthetics he's simply wrong. VI improvers do one thing when it comes to "improving" viscosity: They make an otherwise thinner oil have the viscosity properties of a thicker oil at high temps, and that is the case with synthetic or conventional base oils.
 
But can't you go either way there, G-man? That is, you can start with a thin oil ..and fortify it with VII and make it act thicker at temp ..or start with that weight oil and put PPD in it to make it act like a thinner one at lower temps?? ..or start with a 20W-20 and make it appear like a 10w-30 by doing both (event thought the expense may make this unlikely)??
 
Gary, it may be possible to use PPD's on a 10 cSt blend of base oils to make a multi-viscosity oil - I don't really know the answer.

But, I think Molakule has stated over & over, in regards to viscosity, dino/conventional oils are built up and synthetic formulations are built down.

For dino's that means a 4-5 cSt base oil, a dash of 6 cSt, the additive package and VII's to meet the hot target.

From everything I've read, a PAO synthetic is a blend of multiple viscosity PAO base oils, such as 4-8-20, starting with the high temp viscosity and blending down with the 4 cSt until the low target is reached.
 
quote:

Originally posted by Nick29:
lol @ this thread
Here's thre thread BlazerLT is talking about

http://forums.neons.org/viewtopic.php?t=254042&start=50

there was no misunderstanding among the people he's trying to argue with. He just doesn't understand what they're saying and wants to argue over semantics.
quote:


It isn't that it IS THINNER at cold temps, it is that a particular oil may BEHAVE LIKE A THINNER OIL at cold temp and BEHAVE LIKE A THICKER OIL at high temp.

pretty childish IMO, since a good number of poster on that board post here too.

btw, trex, according to one of AE Haas's articles, dino oils begin as the lower number and have viscosity modifiers added to make them behave like the higher number and synthetics begin at the higher number and have modifiers to make it act like the lower number.


Re-read the thread, there are plenty of people in that thread thinking that oil is thinner when cold than it is when hot HENCE why I said something.

If you think it is childish to help someone find the right answer then everyone here at BITOG I guess are childish then.
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quote:

Originally posted by Gary Allan:
But can't you go either way there, G-man? That is, you can start with a thin oil ..and fortify it with VII and make it act thicker at temp ..or start with that weight oil and put PPD in it to make it act like a thinner one at lower temps?? ..or start with a 20W-20 and make it appear like a 10w-30 by doing both (event thought the expense may make this unlikely)??

Because PPDs do one thing: Prevent/delay the formation of wax crystals in conventional oils at low temps. Esters and PAOs do not respond to PPD treatment since they don't have any wax in them. And I don't care how much PPD you use in a conventional oil, it will never turn a 30wt straight grade into an oil that has the low temp properties of a 5w. No way, no how. (Unless, of course, you use about 50% of 4cSt PAO and call it a "pour point depresent.")

To the extent VI improvers are used in PAO and ester based synthetics, they are NOT used to improve the cold temp properties of the finished oil. VI improvers do one thing: improve the high temp viscosity properties.
 
"racer's" info is not only 10 years out-of-date, but he's the poster boy for Oil Myths and Misconceptions. It's funny to see some people so out-of-touch and think they are experts. Those guys do not fare well when they come here. Unless they are willing to sit down... read and learn, then assimilate the info, those will become frustrated and never "get it". Guys like him who set aside their previous notions and re-learn the basics are the biggest enthusiasts of BitOG. I hope he puts in the effort so he can properly coach the guys on his Neon Forum.
 
Who is Racer?

The guy in the Neon thread?

[ May 13, 2006, 04:51 PM: Message edited by: BlazerLT ]
 
quote:

Originally posted by G-Man II:
Well...there is a kernal of truth in what they are saying. A 5w30 is going to have the cold flow properties of a 5w oil at "cold" temps (-30 by the SAE J300 specs) and will have the high temp flow properties of a 30 weight at "hot" temps (+100 by the SAE J300 specs). So what you have is an oil that acts like a 5w for cold starts and acts like a 30 weight at operating temp.

this is what G-Man II said, i said basically the same thing. so how is my info so wrong? here is a quote of mine from the other board:

"he is not saying the oil is thinner when cold. he is saying a 5w30 has the cold flow properties of a 5 weight when it is cold."

i am agreeing with the statement that a 5w30 has the cold flow properties of a 5 weight oil when cold.

if i am wrong i will concede the topic.
 
quote:

Because PPDs do one thing: Prevent/delay the formation of wax crystals in conventional oils at low temps. Esters and PAOs do not respond to PPD treatment since they don't have any wax in them. And I don't care how much PPD you use in a conventional oil, it will never turn a 30wt straight grade into an oil that has the low temp properties of a 5w. No way, no how. (Unless, of course, you use about 50% of 4cSt PAO and call it a "pour point depresent.")

Well, I don't know where I said anything about esters or PAOs. Nor did I once mention taking a 30 weight and making it look like a 5w
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I recall a discussion that there were two ways to make a multivisc dino conventional oil. The 10 weight ..taken down to it's lowest pumpability (establishing the 10W grade) ..then VII added to it to MAKE it appear like a 30 weight. The other modality was somewhat opposite. That is ..are you maintaining that the only conventional multiviscosity oil are 100% ALWAYS thin base stocks with VII added????

I will dig deep into the archives to find the post by Stinky Peterson who posed the thin basestock with VII added in "co-offering" of how one gets a resultant multivisc dino.
 
quote:

Originally posted by racer12306:

quote:

Originally posted by G-Man II:
Well...there is a kernal of truth in what they are saying. A 5w30 is going to have the cold flow properties of a 5w oil at "cold" temps (-30 by the SAE J300 specs) and will have the high temp flow properties of a 30 weight at "hot" temps (+100 by the SAE J300 specs). So what you have is an oil that acts like a 5w for cold starts and acts like a 30 weight at operating temp.

this is what G-Man II said, i said basically the same thing. so how is my info so wrong? here is a quote of mine from the other board:

"he is not saying the oil is thinner when cold. he is saying a 5w30 has the cold flow properties of a 5 weight when it is cold."

i am agreeing with the statement that a 5w30 has the cold flow properties of a 5 weight oil when cold.

if i am wrong i will concede the topic.


But by saying that, you are still stating that the 5 in 5w30 stands for a weight.

It does not.
 
racer, I got some of your posts confused with others, sorry.


Still-

5wxx oils act like a 5 weight oil at startup

you can use 5w20 in your car, but be prepared for an increase in oil consumption

"Not True" synthetics

???
 
the first one: while correct it is technically wrong, as has been decided in this thread. its just an easy way to state it.

the second one: now that i read it again, i should have worded that better. i should have said watch for an increase consumption.

the third one: people here state that the same way when talking about group 3 synthetics. most people over on neons.org is convinced that group 3 synthetic oils are the devil. i personally dont have a problem with it as long as the price is right, thats just my opinion on it. if you visited over there as frequently as i do you would see where im coming from. its one of those you have to talk their language kind of thing, no disrespect to them but thats just how it is.
 
quote:

Originally posted by BlazerLT:
But by saying that, you are still stating that the 5 in 5w30 stands for a weight.

It does not.


Well what, pray tell, does it stand for then?
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If the 5w in 5w30 doesn't stand for a "weight," then neither does the 30.
 
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