Oil additives in 0w20

[Black02Silverado]

6 hours ago, Grumpy Bear said:

 

Three in a row. You look desperate. 

 

You my friend are indeed a frog. The Kool-Aid drinking variety. 

 

Question. If I have a spot of rust on my fender should I park on the tracks and let the Atchison, Topeka and Santa Fe run over it and see what I can make of the pieces afterwards?

 

 

And there it is.... MISTER you are smarter than that.  Get out of your head and THINK. How smooth can a surface get before it will no longer "WETS". That number was know before 1939. There is a MINIMUM HTHS for MAXIUM WEAR ABATEMENT. It hasn't changed in about 85 years. And it never will. REGULATION however will. And has. And acts in opposition to WEAR. Hardness, yes, also know since WWII. WT**** Terry.

 

 

I understand CAFE, but if the bearing tolerances are different as in tighter than in earlier years, wouldn't it also mean the lubrication for those be changed to benefit them? 

[KARNUT]

All this information is entertaining. If you’re into numbers. I’ve used engines to extreme. I’ve extended oil drains. I just saw another oil brand advertisement for 25K oil changes. My driving has changed so has my change intervals. I’ve had two oil users from new that never changed over my use. They were on extended with Amsoil in the 90s. I had one engine failure not oil related during a heavy pull. My Odyssey a cylinder deactivation engine went 127K miles on 10K oil changes. I half that it’s approaching 158K. It doesn’t use a drop. Engines have been asked to do more. Run hotter, gotten smaller, run higher RPMs and turn off cylinders. Everyone it seems is going turbo charged. Simple logic one would believe either oil has been better a long time since synthetic. Or has improved. I’ve been reading here engines are getting worse, oil is junk. Everyone is in it for just profit. Screw their reputation and customer. I haven’t witnessed any oil related failures in diesel or gas engines. I’ve been around a lot of all kinds of engines. My conclusion can only be I’m doing it right. 

[diyer2]

 

[customboss]

11 minutes ago, diyer2 said:

 

Oh for Pete’s sake you are just throwing him a bone to chew on!

[Grumpy Bear]

4 hours ago, Black02Silverado said:

I understand CAFE, but if the bearing tolerances are different as in tighter than in earlier years, wouldn't it also mean the lubrication for those be changed to benefit them? 

 

How many times has this been asked and answered? 

 

Yes bearing tolerances are different. They are tighter but that isn't the question to ask is it.

 

The bearing CLEARANCES are the same and have been since we quit using poured Babbitt. Thou of clearance per inch of journal diameter within a certain tolerance. 

 

So NO is the answer. 

 

 

[Grumpy Bear]

15 hours ago, customboss said:

Why use a more viscous lubricant if the design doesn’t require it? You have engine test data and UOA to correlate. I did. 

 

WEAR 

 

That few enough words? 

 

Second question is YES.   

 

********************************

 

I have shown you an example of a licensed Dexos1Gen3 5W30 whos' VOA ASTM D6616 is 6.9 cP (8.3 cSt on a 8.3 density) There is no requirement for this test in the license but that value IS the viscosity in the bearing under load and speed and is OUT OF SPEC LOW. 

 

That value is in the middle of the SAE 20 range and a tenth about the SAE 16 spec. 

 

I've show two oils in the 5W30 range that use 0-5 SSI polymers that pass this test remaining in the MIDDLE of the 5W30 100 C viscosity value and are able to pass the Dexos1Gen3 requirements ON PERFORMANCE, although not licensed. 

 

Listen like you care about the truth for this next paragraph....

 

When I don't know what polymer is being used I PERSONALLY go up a grade KNOWING that if they are using OCP and there is the pretty standard 20-25% shear induced D6616 loss; that the 5W40 I chose from a box store will in deed and in fact, in use be running the REQUIRED minimum viscosity IN SERVICE. 

 

********************************

 

So question back at you...

 

WHY NOT use an oil that exceeds? WHY not use an oil that in service is IN SPEC. 

[PunchT37]

.0015 is a very common CLEARANCE for a main or rod bearing. A zero TOLERANCE spec would be .0015. Period.

 

How much benefit is there to tighten up the clearance? Where will it seize?

 

I hear tolerance ALL the time. Never clearance.

[customboss]

5 hours ago, Grumpy Bear said:

 

WEAR 

 

That few enough words? 

 

Second question is YES.   

 

********************************

 

I have shown you an example of a licensed Dexos1Gen3 5W30 whos' VOA ASTM D6616 is 6.9 cP (8.3 cSt on a 8.3 density) There is no requirement for this test in the license but that value IS the viscosity in the bearing under load and speed and is OUT OF SPEC LOW. 

 

That value is in the middle of the SAE 20 range and a tenth about the SAE 16 spec. 

 

I've show two oils in the 5W30 range that use 0-5 SSI polymers that pass this test remaining in the MIDDLE of the 5W30 100 C viscosity value and are able to pass the Dexos1Gen3 requirements ON PERFORMANCE, although not licensed. 

 

Listen like you care about the truth for this next paragraph....

 

When I don't know what polymer is being used I PERSONALLY go up a grade KNOWING that if they are using OCP and there is the pretty standard 20-25% shear induced D6616 loss; that the 5W40 I chose from a box store will in deed and in fact, in use be running the REQUIRED minimum viscosity IN SERVICE. 

 

********************************

 

So question back at you...

 

WHY NOT use an oil that exceeds? WHY not use an oil that in service is IN SPEC. 

1Needlessly holding heat possibly having transient hot spots especially at rings . 

2forcing laminar flow where turbulent flow desired by design to cut heat & assist combustion chamber seal.
3Desired hydraulic pressure out of spec affecting VVT and lifters. 

4reduce levels of pour point and VI additives 

5 traction and mixed layer dynamics more stable for valvetrain and rings 

6 using proper vis and not more than design HTHS allows less additives and multiple straight vis cuts. 

[Black02Silverado]

Found this on the Engine Labs FB page.

 

Have you ever wondered why engine main or rod bearing clearances always seems to be around 0.0025-inch? We wondered the same thing and launched into a search for an educated answer. The classic rule of thumb has always been 0.001-inch for every 1.00-inch of journal diameter. With a typical 350 small-block Chevy, for example, the main journal diameter is 2.448-inches. This jives nicely with that 0.0025-inch clearance. That engine’s rod journal is smaller at 2.10-inch so, in theory, you could run a slightly tighter clearance. Most engine builders set their clearances close to 0.0025 for both as a matter of convenience.

All of this is generally accepted theory but what few people consider is that these bearing clearances rely on a given oil viscosity to maintain the proper hydrostatic clearance which is a fancy way of stating how the liquid oil keeps the crankshaft journal away from the bearing. In the case of this typical 0.0025-inch clearance, conventional wisdom calls for a 10w-30 or 10w-40 oil. If the clearances are larger – around 0.003-inch or more for larger journal engines such as a 455 Oldsmobile, then a thicker oil such as a 20w-50 is generally used to maintain the proper lubrication barrier.

One point worth mentioning is that it’s not a good idea to arbitrarily choose thin viscosity oil based on a whim without knowing the consequences. A thin oil used in applications where oil temperature exceeds 225 degrees (which is not unusual even for street engines under high ambient temperatures) could expose the bearings to additional wear that could have been prevented with a thicker viscosity.

There are a ton of variables that accompany this discussion. Driven Racing Oil has created a generic chart that recommends a given viscosity based on block material (iron vs aluminum), bearing clearance, and engine oil temperature. As an example, an engine with an iron block with 0.0025-inch main bearing clearances that sees oil temperature in excess of 220 degrees would be best served using a 10w-40 or 15w-40 viscosity oil.

 

[PunchT37]

2 hours ago, Black02Silverado said:

Found this on the Engine Labs FB page.

 

Have you ever wondered why engine main or rod bearing clearances always seems to be around 0.0025-inch? We wondered the same thing and launched into a search for an educated answer. The classic rule of thumb has always been 0.001-inch for every 1.00-inch of journal diameter. With a typical 350 small-block Chevy, for example, the main journal diameter is 2.448-inches. This jives nicely with that 0.0025-inch clearance. That engine’s rod journal is smaller at 2.10-inch so, in theory, you could run a slightly tighter clearance. Most engine builders set their clearances close to 0.0025 for both as a matter of convenience.

All of this is generally accepted theory but what few people consider is that these bearing clearances rely on a given oil viscosity to maintain the proper hydrostatic clearance which is a fancy way of stating how the liquid oil keeps the crankshaft journal away from the bearing. In the case of this typical 0.0025-inch clearance, conventional wisdom calls for a 10w-30 or 10w-40 oil. If the clearances are larger – around 0.003-inch or more for larger journal engines such as a 455 Oldsmobile, then a thicker oil such as a 20w-50 is generally used to maintain the proper lubrication barrier.

One point worth mentioning is that it’s not a good idea to arbitrarily choose thin viscosity oil based on a whim without knowing the consequences. A thin oil used in applications where oil temperature exceeds 225 degrees (which is not unusual even for street engines under high ambient temperatures) could expose the bearings to additional wear that could have been prevented with a thicker viscosity.

There are a ton of variables that accompany this discussion. Driven Racing Oil has created a generic chart that recommends a given viscosity based on block material (iron vs aluminum), bearing clearance, and engine oil temperature. As an example, an engine with an iron block with 0.0025-inch main bearing clearances that sees oil temperature in excess of 220 degrees would be best served using a 10w-40 or 15w-40 viscosity oil.

 

True for the most part. .001/inch.  The 455 Olds has a 3 inch main. Like the 351w Ford and the 360LA Mopar. The Caddy 472/500, the Buick 430, 455, and the Pontiac 421,428,455 have a 3.25 main. Even on these, that rule makes these too loose. They will cold knock. Run em in the mid 2`s.

 

That 455, in my avatar,is in the mid 2`s for mains and rods. Steel 4340 rods. I spin this thing to 6400 rpm`s more than it needs. No problems. I mostly run a 10w30 unless I go to the track where it gets a 20w50. That thing makes 630hp and 600 tq.

 

I got that .0015 from the factory manual for the bottom TOLERANCE on mains. Too tight for my liking. Begging for a spun bearing. But, it`s in the tolerance. I didn`t remember the upper tolerance.

 

My b!tch above was about how often I hear about oil weights in tight tolerance engines but I never hear the clearance word for the thin oil argument. YouTube being famous for it in the arguing comments.

Edited February 9, 2025 by PunchT37

[customboss]

23 hours ago, Grumpy Bear said:

 

How many times has this been asked and answered? 

 

Yes bearing tolerances are different. They are tighter but that isn't the question to ask is it.

 

The bearing CLEARANCES are the same and have been since we quit using poured Babbitt. Thou of clearance per inch of journal diameter within a certain tolerance. 

 

So NO is the answer. 

 

 

Piston ring design, cylinder design, combustion chamber design, ignition design, intake design, valvetrain design and LOADS on valve actuation , and finally fuel delivery are ALL different and more advanced than 1939. 
One area you ignore is bearing and other materials design.  Most bearings are not 1939 levels. They use non leaded and less ferritic materials where heat moving is critical. 
Why did Ford change from 5w30 in the modular 4.6 - 5.4- 6.8 family of engines? Carbon deposits and viscosity’s ability to move heat from tight head deck heights so 5w20 solved those issues and STILL protected the aluminum alloy bearings! 

[Grumpy Bear]

Every once in awhile I have to remind the crowd....I DON'T CARE.  It has no impact on my equipment or my bank account. 

 

I'll tell you where the wall is but if you insist on walking into it....

 

Riddle me this Batman. What do I gain in my error? You think someone is subsidizing my writing? Tell me what my gain is by anyone agreeing or disagreeing with me. How do I profit from any of this? I'll be dead in a few years or sooner. Why would I care what you think or what you believe.  

 

Try looking for what is RIGHT instead of CANCELING what doesn't fit your BELIEFS. 

 

If the lube is hydrodynamic then the material doesn't matter, does it.  

 

Nick, take that fancy chart and apply it to some real motors. Then ask yourself what that has to do with REALITY. 

 

 

Use an OBDII reader and STUDY it instead of listening to 'experts'. That chart is two grades plus/minus based on ACTUALL oil temperatures 

 

NO ONE has answered my question. Brand a 5W30 has a D6616 of 8 Cst and Brand B 12 cst. A full grade difference and NONE of you that are not doing the study know which witch is which. And yet you act like you know something you don't. You call yourselves experts? Chemical Engineers? Mechanical Engineers? Lord.....

 

 

 

 

 

 

 

 

 

[Grumpy Bear]

On 2/8/2025 at 5:08 PM, Black02Silverado said:

Found this on the Engine Labs FB page.

 

Have you ever wondered why engine main or rod bearing clearances always seems to be around 0.0025-inch? We wondered the same thing and launched into a search for an educated answer. The classic rule of thumb has always been 0.001-inch for every 1.00-inch of journal diameter. With a typical 350 small-block Chevy, for example, the main journal diameter is 2.448-inches. This jives nicely with that 0.0025-inch clearance. That engine’s rod journal is smaller at 2.10-inch so, in theory, you could run a slightly tighter clearance. Most engine builders set their clearances close to 0.0025 for both as a matter of convenience.

All of this is generally accepted theory but what few people consider is that these bearing clearances rely on a given oil viscosity to maintain the proper hydrostatic clearance which is a fancy way of stating how the liquid oil keeps the crankshaft journal away from the bearing. In the case of this typical 0.0025-inch clearance, conventional wisdom calls for a 10w-30 or 10w-40 oil. If the clearances are larger – around 0.003-inch or more for larger journal engines such as a 455 Oldsmobile, then a thicker oil such as a 20w-50 is generally used to maintain the proper lubrication barrier.

One point worth mentioning is that it’s not a good idea to arbitrarily choose thin viscosity oil based on a whim without knowing the consequences. A thin oil used in applications where oil temperature exceeds 225 degrees (which is not unusual even for street engines under high ambient temperatures) could expose the bearings to additional wear that could have been prevented with a thicker viscosity.

There are a ton of variables that accompany this discussion. Driven Racing Oil has created a generic chart that recommends a given viscosity based on block material (iron vs aluminum), bearing clearance, and engine oil temperature. As an example, an engine with an iron block with 0.0025-inch main bearing clearances that sees oil temperature in excess of 220 degrees would be best served using a 10w-40 or 15w-40 viscosity oil.

 

 

So Nick. You're chart shows the influence oil temp has on viscosity. Good that makes this easy. 

 

So viscosity, not GRADE is the important factor. Let's pick a clearance that asks for a *W30 or 9.3 to <12.5 cSt to make this easier. 

 

Would that be the 5W30 with a Supertech label that has a new D6616 viscosity of 8 cSt? Or a HPL No-VII 5W30  with a D6616 of 11.2 cSt or a Pennzoil 0W40 OCP polymer 500 miles into the run with a D6616 of under >11 cSt? Yes, three GRADES that meet the same viscosity spec. IN PRACTICE. 

 

Now tell me why the manual doesn't state the use of a heavier oil for towing when oil temperatures will be well over 250 F and thinner mid winter under 200 F?

 

Tell my why the 6.2 with the same materials and clearances across several platforms calls out 3 different grades. 

 

Tell me why Mitsubishi England manuals allow of anything between 0W20 and 20W50?   

 

[customboss]

10 hours ago, Grumpy Bear said:

..I DON'T CARE

I care about the truth OF SCIENCE 

[customboss]

10 hours ago, Grumpy Bear said:

Tell me why Mitsubishi England manuals allow of anything between 0W20 and 20W50? 

It’s a worldwide platform. Quality of engine oil in 3rd world countries is poor. Materials science departments of major engine makers have been gutted EXCEPT CUMMINS.