Engine Damage caused from 0W20/5W20?

[ARCOgraphite]

I seriously doubt the tolerances have changed.

I would agree, I just rebuilt a Buick 340 last year and it had tight tolerances AND clearances
likely placed to whatever the materials and machining capability would allow.

You have crank harmonics, core shift and other tolerance stackups coming into play that will pretty much disallow a
anything much tighter than 0.0005" diametrical on plain bearings.
- Ken

 

[RetiredSux]

PM me if you want to chat offline.

Swearing, Political talk, Unqualified Medical advice and viscous, ad hominem attacks may get you a time out, for sure.

But I am not a moderator, nor am I an oil Formulator or "expert"

Most experts are over on the NORIA board this is mainly an "enthusiasts forum, IMHO.

I am here just learning about oil and filters and other stuff - and enjoying the community here;
I've been here for a long time. Came here when I started having "weird" things going on with oil and filters
a couple decades ago.

But, continue to make you argument Sir, don't give up at my counter argument. This is a live discussion.

I do apologize for strafing and then heading right back to base.

- Ken

Good to hear from you! Moving on......

 

[mpack88]

I would agree, I just rebuilt a Buick 340 last year and it had tight tolerances AND clearances
likely placed to whatever the materials and machining capability would allow.

You have crank harmonics, core shift and other tolerance stackups coming into play that will pretty much disallow a
anything much tighter than 0.0005" diametrical on plain bearings.
- Ken

View attachment 47920View attachment 47918View attachment 47919

Tell me about that air cleaner?

 

[PontiacHO]

Looks like a 389 Pontiac breather assembly.

 

[mpack88]

1961 pontiac 389 2 barrel breather air cleaner oem | eBay

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Found one. Does look similar

 

[PontiacHO]

1966 GTO 389 4bbl. carb.

 

[ARCOgraphite]

Tell me about that air cleaner?

That's a GM factory "High performance" air cleaner; meaning "big bog" until warmed up since there is no snorkel heat riser in 1967 non-smog cars

I'm not a fan - but it's factory correct and rare. The car is a rare GS340 A -Body, baby brother to the GS400. Torquey engine.

Better , IMO, than than the later GS big block "Star Wars" Units that looked like this:

 

[ARCOgraphite]

1966 GTO 389 4bbl. carb.

Def looks better on the Poncho!

 

[Jackson_Slugger]

There have been a few studies posted over the years on BITOG that showed increased wear can happen as the HTHS goes below 2.6 cSt. Most xW-20 oils have a HTHS of around 2.6-2.7 cSt and xW-30 around 3.0-3.1 cSt.

This is a good example why you wouldn't want to run a xW-20 in harsh use conditions where there is elevated oil temperature and higher engine RPM. This is why even some vehicle manufacturers in the USA (CAFE driven) still include a statement in the OM to use something thicker than the "recommend" xW-20 when severe use conditions like high speed driving and towing. So I'd say yeah, there is proof that xW-20 can cause increased wear under certain conditions.

View attachment 47868

Which studies and what year were they done? And is it the one where the "experimenters" "formulated" their own 0W-20?

 

[Jackson_Slugger]

I can post several GM manuals where 5W-20 was a recommended winter oil IN THE 1960's!. And ones where 5W-30 "was not recommended for sustained highway operation/driving" up into the 1990's...

The "ever-thinning CAFE oils" paradigm is simply not as easy as you'd like to believe...

 

[PimTac]

I think the definitions of wear and damage are being used in similar fashion in this thread. They are not the same. All engines will have some wear as they are run. Damage is more finite.

 

[willbur]

Do we have any automotive powertrain engineers on this forum anymore? I can’t recall that we do anymore. IMO it would interesting to hear from the actual engineers who designed the engine. The ones who actually use math based equations who come up with every specified detail of the engine, and why they specify a certain oil grade. Alas, engineers of that caliber are almost always under non disclosure or confidentiality contracts with their employer so they can’t go on a public internet forum and start spilling information. Those engineers probably think we’re all crazy lunatics.

We had one that worked on GM power trains and the OLM. He got banned here because he upset some people with his opinions and recommendations. Was pretty good. Wish he was still around

 

[ZeeOSix]

Which studies and what year were they done? And is it the one where the "experimenters" "formulated" their own 0W-20?

There are plenty of studies out there ... many have been talked about here over the years. If people want to do their own research on the subject beyond what's discussed on BITOG, then 10 fingers and Google is all you need. Fact is, viscosity is and always will be the first factor in helping to prevent wear. More than one study has shown that HTHS of 2.6 cSt or less is the point where increased wear is more noticeable in some engine components. AW/AF additives are always changing to keep up with the ever thinning viscosity. Film thickness vs film strength ... it's all an oil formulation game that never ends.

 

[kschachn]

I can post several GM manuals where 5W-20 was a recommended winter oil IN THE 1960's!. And ones where 5W-30 "was not recommended for sustained highway operation/driving" up into the 1990's...

The "ever-thinning CAFE oils" paradigm is simply not as easy as you'd like to believe...

Yes, but that designation then did not mean the same as today's 20-grades. We've discussed that on here before.

 

[Jackson_Slugger]

Yes, but that designation then did not mean the same as today's 20-grades. We've discussed that on here before.

Absolutely correct those 5W-20's were horrible no argument,. But they were Group I...

 

[wemay]

Here (spider graph below) are two Volkswagen approvals. One, 508.00 has a ~2.6 HTHS (0W-20). The other, 505.00 ~3.5 HTHS (0/5W-30, 0/5W-40). The wear ratings are identical.

These approvals can be compared using the Lubrizol Tool because each is a VW Approval, thus falling inside the parameters of Lubrizol's recommended use of said tool.

"Relative Performance Comparison Tool for Passenger Car Specifications - Engine Oil Additives - The Lubrizol Corporation" https://online.lubrizol.com/relperftool/pc.html

Now, this isn't an example of all 2.6 vs 3.5 oils. It's more so an indication of how far the lower viscosity additive technology has come.

My layman's guess plus many years of some manufacturers recommending 20s is that VW508.00 approved oils aren't the only one's offering excellent wear protection. I'd use a dexos1 Gen2, GF-6 (insert Ford's approval) oil with little concern if the vehicle were spec'd to use a 20 (~2.6 HTHS).

In fairness to VW approvals comparisons, I will also add that their new 504.00 approval (~3.5 HTHS) betters both, 508.00 and 505.00 where wear is concerned.

 

[ARCOgraphite]

I can post several GM manuals where 5W-20 was a recommended winter oil IN THE 1960's!. And ones where 5W-30 "was not recommended for sustained highway operation/driving" up into the 1990's...

The "ever-thinning CAFE oils" paradigm is simply not as easy as you'd like to believe...

I don't recall a 5W20 in the 60's. Just a big deal when 10w30 "All Climate" was promoted,

Ford were spec'ing 20 and 20W back in the Fifties, and 10W below freezing.

This is a photo of FORD recommended oil viscosity off a fender tag on a Classic Ford V8 Y-Block, IIRC.

 

[Jackson_Slugger]

I don't recall a 5W20 in the 60's. Just a big deal when 10w30 "All Climate" was promoted,

Ford were spec'ing 20 and 20W back in the Fifties, and 10W below freezing.

This is a photo of FORD recommended oil viscosity off a fender tag on a Classic Ford V8 Y-Block, IIRC.

From a 1968 manual:

Courtesy of: http://www.modifiedcadillac.org/documents/1960s/1968/1968 Owner Manual/

Album: documents

 

[Jackson_Slugger]

From 1960, 10W-30 was preferred overall, 5W-20 could be used below -10F.

By 1974 5W-30 was recommended as an all-season oil in Canada. 5W-20 could be used below 20F, but was not recommended for sustained highway driving...

 

[PimTac]

From a 1968 manual:

Courtesy of: http://www.modifiedcadillac.org/documents/1960s/1968/1968 Owner Manual/

Album: documents

Interesting reference. My recollection from back then was that 10w40 and SAE 30 were the main grades. One could find SAE 40 and 20 but anything else was not too common. This may depend on the region too.

When multigrade oils became the standard that pretty much eliminated the summer/winter grade regimen. Even back then, habits were hard to change.