Polymeric Thickener content and the high temp, high shear test

[TooSlick]

The reason why SAE 0w-40's perform so poorly in this test is directly related to their high polymer content. The HT/HS test uses a tapered bearing simulator and the oil flows through it under high pressure and temp.

As the oil flows through this restrictive bearing orifice, the long chain polymers align themselves in the direction of flow, hence the oil temporarily thins out. The best way to visualize this is to think of what happens when you run a piece of rubber between two steel rollers. As the rubber flows between the roller, it is compressed and then it snaps back to its' original cross sectional area on the other side. For those of you who are engineers or materials scientists, this is roughly analogous to elastic deformation of metals, ie "Hookes Law".

The high temp, high shear test done @ 150C does NOT cause a permanent loss of viscosity (as does the multi-cycle, Bosch Injector test). However, it does tell you how "squeezable"the oil is, which reflects the polymer content.

All things being equal, the more polymeric thickener, the more likely the lube is to shear in actual service....

 

[427Z06]

quote:

---

Originally posted by TooSlick:
The reason why SAE 0w-40's perform so poorly in this test is directly related to their high polymer content.

---

Isn't the descriptive term "poorly" kinda' subjective? If the HTHS value of a particular oil meets the needs of the intended application along with the viscosity, the oil in question could be ideal.

 

[Doug Hillary]

Oh Ted,
you worry so much about 0w-40 synthetic lubricants and shear stability.
Why Ted? Can't you sleep at night? If we changed it to sheer stability would you feel happier?

These SHEAR STABIL 0w-40 oils do a great job as Factory fill lubricants around the world;

Addinol - UltraLight MV
Agip - Tecsint
Aral - Supertronic
BP - Visco 5000
Castrol - Formula RS
DEA - Ultec Syn-T
Mobil - M1 (SuperSyn)
Gruppa Lotos - Lotos Syntetic
Motul - 8100 Ester "E"-Tech
Motul - Synergie Ester+
Novokvibyshevsk - U Tech Sys
Shell - Helix Ultra
Spectr Auto Industries - Prolarm
Valvoline - Synpro
Valvoline - Synpower
Westfalen - Gigatron

There are more too - no Amsoil products of course because they THICKEN don't they!

You have NOT produced the worn out engines caused by excessive wear in valve trains etc. And you won't Ted because they don't exist!

0w-40 synthetic oils go in to millions of new cars annually and function with excellent results! No unusual Warranty claims arise even with extended unlimited distance Warranties. Many are suitable for extended drians too Ted!!!

Oh and SHEAR STABILITY and the HTHS protocols should be broken down;

(Global Performance Specifications - ACEA)
1 - Engine oils that contain polymers typically undergo viscosity loss when subjected to high shear conditions. High shear regimes in an engine exist in piston ring and cylinder wall interface, valve train and other areas of high relative parts velocity, high loading and/or high temperature. Shear stability is measured by ASTM D6278, which accommodates the European CEC L-14-A-93 technique. Shearing which results in a permanent loss is evaluated in this test by pasing fresh oil through a high shear fixture, followed by measuring kinematic viscosity (ASTM D445). Engine oil producing a test result below a prescribed limit may not maintain sufficient oil film thickness in heavily loaded areas of the engine.

2 - Bench Tests
Shear Stability
The Standard Test Method for Shear Stability of Polymer-Containing Fluids using a Diesel Injector Nozzle, ASTM 6278 or CEC L 14-A-94, measures the percent viscosity loss at 100C of polymer containing fluids when evaluated with a Bosch PE 2A 90c300/3S2266 double plunger injection pump connected to an atomization chamber equipped with a Bosch DN 8 S2 pintle nozzle injector

High Temperature/High Shear Rate Viscosity
Three test methods are listed for measurement of this property, consistent with the SAE J300 viscosity classification. Each method evaluates engine oil viscosity by subjecting it to conditions of high shear rate (1 x 10/6s-1) and high temperature (150C)
ASTM D4683 and CEC L-36A-97 utilises a motor driven tapered rotor tapered rotor that is closely fitted in a matched stator. The rotor exhibits a reactive torque response when it encounters a viscous resistance from an oil filling the gap between the rotor and stator. The unit is calibrated with a reference oils

ASTM D4624 utilises a capillary viscometer which responds to the apparent shear rate at the walls of the capillary as determined by the pressure drop and flow rate through the capillary under desired conditions. The unit is calibrated with a reference oils

3 - Engine Tests
Seven engine were used in this case
The maximum sustained engine oil temperature test (CEC L-88-T-02) is 150C for 72 hrs
The VW TDI test (CEC L-78-T-99) is for 54 hrs at maximum load at 4150rpm and 145C oil temperature
The VW TDI Intercooler test (CEC L-46-T-93) is for 50 hrs at full speed (4500rpm) and at 130C oil temperature
Th MB OM602A test (CEC L -51-A-98) is for 200 hrs and up to 142C oil temps

You only mention one HTHS bench test Ted, and the most common engine test was to monitor engine oil THICKENING! How about that Ted!!!

So relax Ted, 0w-40 oils that have a Manufacturer's Approval and are listed are truely wonderful lubricants. They have proved themselves for nearly a decade. Now if they shear to a high SAE30 over time is that really critical? No Ted it is not!
In the real world testing done by the German engine makers, they use the above Standard Test(s) in their own extended Test Protocols. No pass = no Approval!

And Ted not a four balls test in sight!!!!

Keep smiling

Regards
Doug

 

[goodvibes]

Now that you mention it Amsoil does make a 0w40. It will shear like the rest but maybe it will thicken while it's shearing and stay closer to grade.

I think maybe what he's getting at is that it's actually a 30w oil with thickeners added so treat it like a 30 and not a 40. Nothing wrong with a good 30 in most apps. Just know what your getting and don't forget that it doesn't shear in every instance.

 

[Bryanccfshr]

I just love the Ted and Doug discussions

... you gonna take that from him Ted? J/K

The thing I like most about this forum is for the most part brand is less important than the technology.

Ted your observation makes sense but I can't see it making a real world difference.

Yes, 0w40 is not gonna stay as viscos as an HDEO 40 wt would but the 0w40 is designed for a specific purpose and perhaps the engine makers know exactly what they are doing when they make the recomendation for this oil..... perhaps these engines perform beter with a lighter40 wt or havy 30wt oil but the european market would not abide by a 30 wt recomendation.

Who doesn't know that M1 formualtions are light?

It is niice to have the choice on what to run with all the knowledge available at BITOG. If all oil formulators had the same target viscosities how would e fine toon for our applications?

 

[1911]

quote:

---

Originally posted by TooSlick:
. The best way to visualize this is to think of what happens when you run a piece of rubber between two steel rollers. As the rubber flows between the roller, it is compressed and then it snaps back to its' original cross sectional area on the other side. For those of you who are engineers or materials scientists, this is roughly analogous to elastic deformation of metals, ie "Hookes Law".

---

Ted,

No disrespect but your attempt at analogy between the concept of viscosity and the elastic modulus of solids is ridiculous. What are you talking about with this "squeezability" or stiffness nonsence? Ted, a wake up call for you bro......we're talking about a liquid here and elastic moduli (either the Young's modulus "E" or shear modulus "G") have no meaning for a liquid which by definition continually flows under a fixed load. Therefore, a fixed deformation or strain cannot be ascribed to a given load and thus, there is no such thing as stiffness which is load divided by a fixed strain!!! You know better.....the others know better, so let's knock off the improper and poorly chosen analogies. Viscosity concerns itself with the shear stress levels necessary to create a given flow rate gradient in a liquid. It has no relation to "squeezability".

Please refrain from defiling the Materials Engineering Department at Georgia Tech on this board with poor analogies.

1911

 

[DR Racing]

I have to agree with Ted. I believe in running as little polymeric thickeners as you can get away with. They leave more deposits, shear and don't lubricate. I see them as a necessary evil because cold weather does exist. If your climate does not warrant a 0w-40 then don't use it. Use as high an xw as you need for the climate that you will be in. Dan

 

[Audi Junkie]

Don't squeeze the Charmin! Can anybody take a shot at the physicality behind oxydative thickening in regards to lubrication of an I-C-E? Just wondering.

 

[Pablo]

Again Doug you go personal. Why do you have to do this?

First of all you make a great argument for getting factory fill 0W-40 out ASAP - I think the only reason the 0W-40 oils don't ruin millions of cars is because the cars are well made and would do fine even on a 0W-20 so as the others point out the shearing has no fast real world implication.

Second, sure some Amsoil oils thicken. Why do you lose so much sleep over this Doug? Why bring it up? Have you ran out of ammunition? Facts are that a slight thickening seems to have no real effect on wear numbers.

Lastly in Teddie's defense he wrote "roughly analogous".....and I believe he is talking at the molecular level about the long chain polymers breaking. The armchair critics called this "nonsence"....

I call it reality.

 

[Doug Hillary]

Hi DR Racing,
Ted said: "All things being equal, the more polymeric thickener, the more likely the lube is to shear in actual service...."

He is probably correct but he was referring selectively to probably the most popular new engine synthetic oil fill - 0w-40. The grade with a good in-service history!

He was not commenting on mineral oils and the likes of Castrol's "R" 10w-60 and the many others with a wider viscosity spread. There are many and in that regard he is probably correct

You said: "I believe in running as little polymeric thickeners as you can get away with."

I agree with you but no substantive evidence of poor viscosity performance exists regarding 0w-40 synthetic oils meeting A3/B3/B4 and MB, Porsche, VW and BMW Test protocols. They either pass the Test or they don't!!!

Therefore, IMHO Ted's comments;
"The reason why SAE 0w-40's perform so poorly in this test is directly related to their high polymer content." - needs to be substantiated!

"Perform so poorly"? - they must satisfactorily pass the Test protocol so when do they perform poorly????
When they don't pass the Test? - then, they have failed the Test!!!

Oh Ted don't worry about it so - the only thing is that they (0w-40 synthetics) just won't go away!!

Come on down here to OZ Ted and have a day or three relaxing, a nice Merlot or Shiraz or two and some Barramundi, Kangaroo or Crocodile steaks from the BBQ. Or even a good environmentally bred beef steak perhaps....

Regards
Doug

 

[moribundman]

I was having a delicious Vegemite sandwich while reading this thread. Now, an oil passing a specific test doesn't really make that oil a top performer, does it? It makes it an oil that passed. Certainly we can do better! At least that's what my teacher would've said to me when I got a passing grade.

 

[427Z06]

Since we have a lot of smart people here I have a question. Do polymeric thickeners used in oil provide any additional lubricity during mixed film or boundary lubrication states like they do in aqueous hydraulic fluids?

moribundman, you just popped one of my brain cells:

Traveling in a fried-out combie
On a hippie trail, head full of zombie
I met a strange lady, she made me nervous
She took me in and gave me breakfast
And she said,

Do you come from a land down under?
Where women glow and men plunder?
Can’t you hear, can’t you hear the thunder?
You better run, you better take cover.

Buying bread from a man in brussels
He was six foot four and full of muscles
I said, do you speak-a my language?
He just smiled and gave me a vegemite sandwich
And he said,

I come from a land down under
Where beer does flow and men chunder
Can’t you hear, can’t you hear the thunder?
You better run, you better take cover.

Lying in a den in bombay
With a slack jaw, and not much to say
I said to the man, are you trying to tempt me
Because I come from the land of plenty?
And he said,

Oh! do you come from a land down under? (oh yeah yeah)
Where women glow and men plunder?
Can’t you hear, can’t you hear the thunder?
You better run, you better take cover.

 

[moribundman]

I love that song!

 

[Doug Hillary]

Hi Moribundman,
I'm pleased that you like Vegemite

Vegemite comes in a Passed Extra Taste Test version here now! Its performance is much better too - it's simply tops!

I hope we both passed the grade..............

427Z06 - yes that brings memories of Alan Bond, winged keels and a certain America's Cup!
Oh well at least it never had a sinking feeling like our last attempt at San Diego

Regards
Doug

 

[moribundman]

Very funny, Doug!

 

[Bryanccfshr]

quote:

---

Originally posted by 427Z06:
Since we have a lot of smart people here I have a question. Do polymeric thickeners used in oil provide any additional lubricity during mixed film or boundary lubrication states like they do in aqueous hydraulic fluids?

moribundman, you just popped one of my brain cells:

Traveling in a fried-out combie
On a hippie trail, head full of zombie
I met a strange lady, she made me nervous
She took me in and gave me breakfast
And she said,

Do you come from a land down under?
Where women glow and men plunder?
Can’t you hear, can’t you hear the thunder?
You better run, you better take cover.

Buying bread from a man in brussels
He was six foot four and full of muscles
I said, do you speak-a my language?
He just smiled and gave me a vegemite sandwich
And he said,

I come from a land down under
Where beer does flow and men chunder
Can’t you hear, can’t you hear the thunder?
You better run, you better take cover.

Lying in a den in bombay
With a slack jaw, and not much to say
I said to the man, are you trying to tempt me
Because I come from the land of plenty?
And he said,

Oh! do you come from a land down under? (oh yeah yeah)
Where women glow and men plunder?
Can’t you hear, can’t you hear the thunder?
You better run, you better take cover.

---

Thanks for bringing back a nice song from a decade of good music.

 

[TooSlick]

1911,

In retrospect, it was a VERY poor analogy....My old British advisor, Dr. John T. Berry, must be turning in his grave somewhere...

I can almost hear him say: "Bugger That!", if I came up with a lecture like the one posted above.

The tribological principles I attempt to explain (sometimes poorly) are general guidelines of oil formulation. They are not intended at any one specific product and would be true regardless of who formulates a 0w-40 in this case.

"Dr. Doogie",

At least in the short term, I've decided on Costa Rica for our 14th Anniv. this year. I'm still planning a trip your way sometime in the near future (while I can still remember who you are) LOL!

regards,

Ted

 

[drums57]

All i can say is i got better oil consuption with Wolfshead 10w30 than with Mobil 1 0w40 in a ford F150 with a 302 v8. Can anyone tell me why , read Ted's first post and you will know why.

 

[Doug Hillary]

Hi Ted,
you are very welcome here - seriously!

We do get visitors here from the Porsche family around the world. Most Ozzies love our friends from the US and you will be well accepted here

Remember?

"I rememeber you
You're the one who broke my car in two
Didn't you?"

and etc.......

Pabs thinks it's personal - how could he Ted?
We lubbs ya!!!

drums57 - oil consumption is another issue. IMHO I prefer an engine to consume a little oil especially with OCIs out to 20kkms or so

Keep happy 'n smilin'
Regards
Doug

 

[TooSlick]

Mobil 1, 0w-40:

Kinematic (low shear rate, unconstrained) viscosity @ 100C, 14.4 Cst
HT/HS viscosity @ 150C, 3.6 Cp
VI, 185 (can't do this without about 0.5%-0.7% polymeric thickener)

Delvac 1, 5w-40:

kinematic viscosity @ 100C, 14.8 Cst
HT/HS viscosity @ 150C, 4.1 Cp
VI, 151 (0.0% polymer)

The SAE 0w-40/5w-50 grades are a customer driven (one size fits all) idea, but they're poor polymer chemistry...