Why does the 4.3l use 5w-30 oil and the 5.3l use 0w-20?

customboss · October 15, 2022

11 hours ago, Grumpy Bear said:

What? Okay a slave cylinder will move slowly when the oil is like -30F and viscosity is 60,000 cP. Pushing peanut butter instead of hot honey, but the difference of even 20 cSt at 212 F would not even be measurable. The difference between an SAE 20 min and an SAE 60 max. There is more difference between 100 F and 212 F. More difference between running an oil cooler maintaining 190 F and unregulated at 250 F. C'mon.....

Besides. Timing LIMITS are controlled by the mechanical RANGE and not how quick the fluid moves. Pressure isn't influenced by viscosity. A 1 cP cup of water will transmit the same PRESSURE as a steel rod. This isn't a system pushing fluid through a sub-fractional orifice. It's pumping oil through the Holland tunnel balance against a spring.

Bet I get the same hydraulic PRESSURE at -25F as I do at 125F air temp. Gezz, don't tell my brakes this. They will quit working. Note viscosity vs temp of brake fluid below.

Riddle me the design dynamic vis range for GM cam phasing, VVT, AFM operations, in each of the engine designs?

DEXOS limits and requirements was designed to try to corner a stable dynamic vis for GM engines.

Brake fluids are mostly glycol and ether based... Brakes and clutch slave cylinders using a glycol ether usually. Not germane to this discussion.

We are talking about an engine oil to act as a reliable hydraulic fluid with contaminants being added at every cylinder firing.

Clean engine oils aren't clean after a few cycles of rotation and fire. VVT is what drives EGR now, raw fuel, carbon, poor quality fuel additive polymers, and the GM loving nitrous oxides are added into engine oil almost as a NOx wick that will acidify the oil and depending on chemistry thicken or thin it. Cold start performance is completely changed by by these contaminants. There's a battle between acidity, nitration, oxidation, sulfation, and anti wear additives being depleted at a high rate even when the PPM of them in oil analysis shows their leftovers as high. Why Nick tests for AW in FTIR and does not rely on just the wear and additives metals testing.

Once a desired hydraulic range is set by GM they moderate that with ECM sensing and controlling via cam phaser solenoids. Tell me what happens when that desired hydraulic range is lower or higher than the ECM can control for. You saw this is spades with your 2.4.

Every VVT cam phased engine is susceptible to this issue.

The OP is seeing this issue in his modern 4.3 I suspect.

customboss · October 15, 2022

This audi VW focused video is germane to the L3B but the general functions are good to review. "ALL CAM PHASING IS CONTROLLED BY OIL PRESSURE". 4:28 into video. So if you have 3% fuels dilution in the oil you are now asking the ECM and associated solenoids etc to WORK REAL HARD, MAYBE LOSING CONTROL AFFECTING ALOT OF COMBUSTION CONTROL.

pokismoki · October 15, 2022

what a nightmare....

why doesnt audi utilize the camless engine tech out of europe? i guess no one want to pay royalties to the designer...

Edited October 15, 2022 by pokismoki

Grumpy Bear · October 18, 2022

On 10/15/2022 at 11:26 AM, customboss said:

Riddle me the design dynamic vis range for GM cam phasing, VVT, AFM operations, in each of the engine designs?

Riddle me this.

How much density weighted viscosity range is there in the 100C viscosity spec of a *W30 oil? Answer 12.5 - 9.3 = 3.2 cSt.

How much range between mid W30 and W20? 3.45 sCt

How much temperature induced range is there between a *W30 running 1500 rpm and one running 2000 rpm. Oil temp will increase 5 to 9 F and viscosity will drop about 3-4 cSt. A grade.

Don't answer this unless you've measured it. I have. How much difference is there in bulk oil temperature between mid winter and mid summer? About 15 F. And how much viscosity change is there in that span? More than a grade.

How much bulk oil temperature difference between QSUD 5W30 and Red Line 5W30 ( this I have also measured).

And how much range is there between the heaviest *W20 and lightest *W30? Answer 0.1 cSt,

The facts argue against you.

There is more inherent viscosity variation within the spec grade, across the seasons, across operating conditions and across 5% fuel dilution than between three SAE grades.

I what the believe was actually true then not only would there be a viscosity grade spec but a limited season, speed, load, condemned point..... You would not be able to run an oil cooler.......Couldn't run different grade on track day without changing cam phase induced power/torque..... Running 45 on a winding road vs 80 on the Interstate would set it off to limp mode....

There are differences and then there are differences the matter. This one doesn't.

customboss · October 18, 2022

2 hours ago, Grumpy Bear said:

Riddle me this.

How much density weighted viscosity range is there in the 100C viscosity spec of a *W30 oil? Answer 12.5 - 9.3 = 3.2 cSt.

How much range between mid W30 and W20? 3.45 sCt

How much temperature induced range is there between a *W30 running 1500 rpm and one running 2000 rpm. Oil temp will increase 5 to 9 F and viscosity will drop about 3-4 cSt. A grade.

Don't answer this unless you've measured it. I have. How much difference is there in bulk oil temperature between mid winter and mid summer? About 15 F. And how much viscosity change is there in that span? More than a grade.

How much bulk oil temperature difference between QSUD 5W30 and Red Line 5W30 ( this I have also measured).

And how much range is there between the heaviest *W20 and lightest *W30? Answer 0.1 cSt,

The facts argue against you.

There is more inherent viscosity variation within the spec grade, across the seasons, across operating conditions and across 5% fuel dilution than between three SAE grades.

I what the believe was actually true then not only would there be a viscosity grade spec but a limited season, speed, load, condemned point..... You would not be able to run an oil cooler.......Couldn't run different grade on track day without changing cam phase induced power/torque..... Running 45 on a winding road vs 80 on the Interstate would set it off to limp mode....

There are differences and then there are differences the matter. This one doesn't.

Brother Grumpy how did you measure dynamic in-situ viscosity INSIDE YOUR ENGINES ABOVE? I have but not outside of an engine stand and lab.

Published viscosities, label viscosities, spec viscosities, even lab measured oil sampled viscosities do NOT FULLY REPRESENT what an engines sees dynamically. They are a guide and guess but thats it.

customboss · January 4, 2023

For the more in depth thinkers.....

Ionic fluids using electrical field to vary viscosity in situ?

Tribotronic control of an ionic boundary layer in operando extends the limits of lubrication

https://www.nature.com/articles/s41598-022-22504-6

Grumpy Bear · January 4, 2023

On 10/18/2022 at 6:23 PM, customboss said:

Brother Grumpy how did you measure dynamic in-situ viscosity INSIDE YOUR ENGINES ABOVE? I have but not outside of an engine stand and lab.

Published viscosities, label viscosities, spec viscosities, even lab measured oil sampled viscosities do NOT FULLY REPRESENT what an engines sees dynamically. They are a guide and guess but thats it.

You are making this needlessly more complicated that it is. The oil doesn't behave 'differently' between in the motor or on the bench. It's viscosity behavior responds to density, temperature and shear. It has no idea where it is. Density doesn't change because of its place in the universe, not temp or shear. Dynamic in-situ viscosity depends not one iota on location. Science isn't magic.

There is nothing in the below quote that should confuse anyone with enough education to read it. You argue 'hydraulic' is the reason for grade and pin that to viscosity. I simply showed that is not true.

Ever work a dyno and play with cam position? If so, then you know that the viscosity change in even two SAE grades has less effect on power and torque of a VVT than 2* advance or ******...4* total. Tortional, chain a belt induce more dynamic response.

On 10/18/2022 at 3:42 PM, Grumpy Bear said:

Riddle me this.

How much density weighted viscosity range is there in the 100C viscosity spec of a *W30 oil? Answer 12.5 - 9.3 = 3.2 cSt.

How much range between mid W30 and W20? 3.45 sCt

How much temperature induced range is there between a *W30 running 1500 rpm and one running 2000 rpm. Oil temp will increase 5 to 9 F and viscosity will drop about 3-4 cSt. A grade.

Don't answer this unless you've measured it. I have. How much difference is there in bulk oil temperature between mid winter and mid summer? About 15 F. And how much viscosity change is there in that span? More than a grade.

How much bulk oil temperature difference between QSUD 5W30 and Red Line 5W30 ( this I have also measured).

And how much range is there between the heaviest *W20 and lightest *W30? Answer 0.1 cSt,

The facts argue against you.

There is more inherent viscosity variation within the spec grade, across the seasons, across operating conditions and across 5% fuel dilution than between three SAE grades.

I what the believe was actually true then not only would there be a viscosity grade spec but a limited season, speed, load, condemned point..... You would not be able to run an oil cooler.......Couldn't run different grade on track day without changing cam phase induced power/torque..... Running 45 on a winding road vs 80 on the Interstate would set it off to limp mode....

There are differences and then there are differences the matter. This one doesn't.

customboss · January 4, 2023

30 minutes ago, Grumpy Bear said:

It's viscosity behavior responds to density, temperature and shear. It has no idea where it is.

True but our engine oils in our current engines are affected by hydraulic actions the engine oil is controlling with electronic functions. That engine oil density, temp, shear, is all affected by contaminants in the engine oil since the pistons are sucking air and fuel into a common cylinder area we call the combustion chamber.

The oil film on the rings sees more than just out of the bottle viscosity readings you listed above in your graphs.

Dynamic viscosity is more nuanced than the oversimplifications you are confusing us with.

Your bottle of fully formulated lubricant changes once you introduce air, fuel, and fire to it.

Grumpy Bear · January 4, 2023

4 hours ago, customboss said:

True but our engine oils in our current engines are affected by hydraulic actions the engine oil is controlling with electronic functions. That engine oil density, temp, shear, is all affected by contaminants in the engine oil since the pistons are sucking air and fuel into a common cylinder area we call the combustion chamber.

The oil film on the rings sees more than just out of the bottle viscosity readings you listed above in your graphs.

Dynamic viscosity is more nuanced than the oversimplifications you are confusing us with.

Your bottle of fully formulated lubricant changes once you introduce air, fuel, and fire to it.

Progress. And true. It changes as it is used. It's why we need to change is periodically. BUT the significance of those changes' pails IN NORMAL USE over a NORMAL OCI in a NORMAL MOTOR to the changes experienced over a warmup cycle. Over one SAE grade. I'm not confusing anyone with anything.

Science isn't an output. Science isn't the variables that allow an engineer to calculate or measure an output. Science is the STABILITY in SYSTEM that PERMITTS those variables to be distilled into the calculations and measurements by scientific method. Viscosity does not exist because it can be measured. It can be measured because it exists.

Think on this. You can't come to the conclusions you are coming to without saying the system can be measured and if it can then it is 'stable' enough to permit development of the measurement system being used. If those two things are true, then your later conclusion is false. If former is false, then you have no basis for an argument.

Now THATS. confusing.

No one's VVT is "operating outside design" due to 3.5 cSt of viscosity.

customboss · January 4, 2023

47 minutes ago, Grumpy Bear said:

Progress. And true. It changes as it is used. It's why we need to change is periodically. BUT the significance of those changes' pails IN NORMAL USE over a NORMAL OCI in a NORMAL MOTOR to the changes experienced over a warmup cycle. Over one SAE grade. I'm not confusing anyone with anything.

Science isn't an output. Science isn't the variables that allow an engineer to calculate or measure an output. Science is the STABILITY in SYSTEM that PERMITTS those variables to be distilled into the calculations and measurements by scientific method. Viscosity does not exist because it can be measured. It can be measured because it exists.

Think on this. You can't come to the conclusions you are coming to without saying the system can be measured and if it can then it is 'stable' enough to permit development of the measurement system being used. If those two things are true, then your later conclusion is false. If former is false, then you have no basis for an argument.

Now THATS. confusing.

No one's VVT is "operating outside design" due to 3.5 cSt of viscosity.

Who agreed 3.5 cSt delta is the fact?

You are wrapping yourself into knots about this. Not needed! You are respected for your sharing and intellect so don't take this wrong.

As you have shared here in your own experience you ran a 2.4L GM Ecotec 4 cylinder engine using all your assumptions about engine oil and maintenance. You over-fueled for a long time running bottled engine oil that you assumed was just fine.

It built fuel engendered deposits from that over-fueling that nearly cratered that engine. Disclaimer for you....... I agree the piston design is a contributor but I had customers for years that used that engine with NO ISSUES who kept it tuned ideally via oil analysis to get an early warning of problems. SO, .....

Fuel interrupted all the assumptions about viscosity and engine oil you had until you tested the oil. All I am stating is that our engines are hydro electronically controlled for VVT and that if you thin or thicken the oil it will affect the engine. To the point of degrading the engine.

Normal? I don't think so. Every VVT DI engine today is not running normally. It's using defective ( IMHO) fuels and stressing the living lipstick out of the recommended engine oil.

Depending of fuels dilution, engine tune condition, crankcase venting, quality of engine oil and maybe the ability of the engine oil to clean some using assumptions about normal might have an engine nearly fail.

Grumpy Bear · January 5, 2023

What part of.....

5 hours ago, Grumpy Bear said:

IN NORMAL USE over a NORMAL OCI in a NORMAL MOTOR

...floated past you?

Look. Oil isn't black magic. It's a fluid that keeps two parts moving in different directions or even the same direction at different rates, apart. Basic Stribeck. 5%+ fuel in the oil is not NORMAL and yet even THAT motor did not show abnormal wear at the reduced viscosity UNTIL that abnormal state caused ring SHELAC STICKING. Which once freed, reduced wear to normal rates even with 5% and even 8% fuel remaining until that problem was eventually solved.

Cam VVT didn't freak out. Still pasted EPA and MPG. In fact, OBDII diagnostics couldn't even find an issue. Stay on task and topic. Your claim is a 'different grade' will cause crazy hydraulic issues that will disrupt normal VVT/VVL operation. Not true.

Now having said that. The OEM are running a Stribeck low side razors edge, and I would not, without knowledge, run a lower API grade oil but go higher without a thought. With knowledge, and I have some, I know that I can run lower if I reduce bulk temperature enough to cover the curve and have all my life. I run 10W40 and allot of cooler in air cooled motors even when the BOOK calls for 20W60. I just don't tell others to do so.

customboss · January 5, 2023

12 hours ago, Grumpy Bear said:

What part of.....

...floated past you?

Look. Oil isn't black magic. It's a fluid that keeps two parts moving in different directions or even the same direction at different rates, apart. Basic Stribeck. 5%+ fuel in the oil is not NORMAL and yet even THAT motor did not show abnormal wear at the reduced viscosity UNTIL that abnormal state caused ring SHELAC STICKING. Which once freed, reduced wear to normal rates even with 5% and even 8% fuel remaining until that problem was eventually solved.

Cam VVT didn't freak out. Still pasted EPA and MPG. In fact, OBDII diagnostics couldn't even find an issue. Stay on task and topic. Your claim is a 'different grade' will cause crazy hydraulic issues that will disrupt normal VVT/VVL operation. Not true.

Now having said that. The OEM are running a Stribeck low side razors edge, and I would not, without knowledge, run a lower API grade oil but go higher without a thought. With knowledge, and I have some, I know that I can run lower if I reduce bulk temperature enough to cover the curve and have all my life. I run 10W40 and allot of cooler in air cooled motors even when the BOOK calls for 20W60. I just don't tell others to do so.

We disagree and I use your own engines as proof. Your 2.4 needlessly wore over the time you were flying blind.

0.5% or less is normal fuel in oil for ANY IC engine. How many oil analysis results using GC show that?

Normal in your mind is not normal in reality via testing of hundreds of oil analysis results over 40 years of testing.

You aren't grasping my claim. Damaging your engine oil WILL AFFECT cam phasing and FUELING an insidious cycle. Your own units proved that.

Relax Grumpy Bear, we disagree again. SAE viscosity is totally incongruent with what I am speaking to.

You can't measure dynamic viscosity and your posts of pretty charts and graphs mean little based on a bottle claim of SAE vis.

customboss · January 5, 2023

On 1/4/2023 at 8:50 AM, customboss said:

For the more in depth thinkers.....

Ionic fluids using electrical field to vary viscosity in situ?

Tribotronic control of an ionic boundary layer in operando extends the limits of lubrication

https://www.nature.com/articles/s41598-022-22504-6

Bump for Grumpy Bear to focus on something new. Ionic lubricants that use a electrical field to vary vis in situ. Dynamic vis varying in use......

KARNUT · January 5, 2023

My 2 cents. I appreciate the knowledge of the banter. Following Grump's threads with the results accomplished especially with the problem engine. I would lean toward his conclusions. The paper analysis makes my head hurt. I can’t drive paper.

Grumpy Bear · January 6, 2023

23 hours ago, customboss said:

We disagree and I use your own engines as proof.

Dizzy's engine was proof of 'normal operation'? :crackup: Not! You missed the decimal by a spot. 5% (not 0.5%), undetected over tens of thousands of miles and hunted for the source for tens of thousands of more. Nothing NORMAL about that.

These three motors, 5.3, 6.2 and 4.3 use the same parts. Same lifters. Same VLOM components. Same phaser components. Same oil pump. Same oil pump control solenoid. Shall I get the GM part numbers for you? If they all use the same parts, we can KNOW the heat treat and surface finishes are identical which sets asperity height and THE major variable in Stribeck when velocities, load and heat are by design the same or nearly so.

VVT was not and is not a consideration. GM Managment goals are.

On 10/12/2022 at 7:06 AM, Jayselectricco said:

From my understanding the 4.3l ecotec is pretty much the same as the 5.3l ecotec minus 2 cyl. So why are they listed using different oil weights?

Thier reasoning, in this case, is not based on engineering. It's based as I said on GM management goals.

Check out the oil guides for the Camaro and Vette. Different oils for different service. That is engineering based.