BREAKING: GM is officially recalling the L87

[BacDoc]

Я проехал 700 миль на масле 0-40 во время обкатки, после чего залил 0-20. Похоже, версия о том, что надо лить масло 0-40 подтверждается, при 0-40 давление высокое, а при 0-20 примерно в два раза ниже. Подтверждают ли это фотографии? Но нет, фанаты этого фильма, не все так просто) после обкатки я залил ровно то же самое масло, на котором проехал 75 000 миль на своем предыдущем двигателе, это масло бельгийской фирмы Wolf 0-20 dexos. Зачем я все-таки залил 0-20. Я общался с Сервисом, который мне делал этот двигатель. Все, кому они делали двигатель, ездят на масле 0-20, а пробег на новом двигателе уже большой. Так вот, мне залили масло 0-20, я немного покатался, прогрел, проехал по небольшому участку трассы со скоростью 70-80 миль в час, и вот какое у меня давление на масле 0-20. Чудеса. оно около 300 кПа. Я даже выложу рядом фото давления масла 0-40 и 0-20))) на 0-20 оно просто чуть ниже. ну около 300 кПа на 0-20 и может 320 кПа на 0-40. Мое мнение, что либо программное обеспечение изменилось и GM увеличили давление масла, либо это новая доработка масляного насоса. Но масло на давление практически не влияет. На моем новом двигателе давление явно выше, чем на предыдущем.

Took the words right out of my mouth!
I was going to post the same thing! LOL

 

[BacDoc]

What industry is that?
Asking for a friend.

Money for nothing and the chicks are free!

Im guessing politician!

 

[Scarey]

It’s clear that there was a manufacturing defect. No the 20wt oil didn’t cause the failure. But there is allot of evidence showing 40wt could/will slow the damage from the faulty manufacturing. It is also obvious there is a push industry wide to using lighter wt oil to improve mpg. It’s a compromise, slight edge in mpg for a slight decrease in wear reliability. It’s the way our economic system works, looking for the balanced compromise.

 

[Vladimir2306]

Took the words right out of my mouth!
I was going to post the same thing! LOL

Something went wrong, and my browser translated the text into Russian, and published it that way)))

 

[blanchard7684]

So it's a conspiracy?

Do you have data to back your claims? Or just feels ?

I get that many of the less than factual posters get their feelings hurt but all I'm doing is being objective with real data and facts to keep the discussion relevant.

If you would rather it be based on feelings we can do that but we lose the value of discussion.

Here's some reading if you care to enlighten yourself on your misguided logic.

Displacement on Demand

In the quest for better fuel mileage and emission production from the internal combustion engine, new technologies have emerged. One such technology is Displacement on Demand ...

www.vehicleservicepros.com

Cylinder Deactivation - What Is It And How Does It Work?

Learn about the tech of cylinder deactivation in this in-depth article. Discover how it works and why it's important for fuel efficiency.

driving.ca

Theres engineering that goes into these systems. It's not 'feels'

Everyone that says otherwise has something to sell you. And hey capitalism is what we are all about. But to think otherwise is foolish.

Our duramax also uses 0w-20 wonder why it doesnt blow up? Or the millions of other engines that use it? Probably a conspiracy

Stribeck curve

Lubrication Fundamentals

www.stle.org

Sommerfeld number and journal eccentricity

https://rotorlab.tamu.edu/me626/Notes_pdf/Notes04%20Static%20Load%20JBs%2010.pdf

There are a half dozen articles from sae describing development of 0w20. You can find those yourself.

Spoiler alert: all of the research was done for fuel economy.

Getting cute with oil viscosity to save 1 mpg is only bargaining with safety factor in the journal bearings.

( not to mention there is plenty of research showing thinner oils can reduce ring seal)

one little blip in polishing or manufacturing and **** here we are.

You’ll note that one of the countermeasures is changing to 0w40.

Secondly, dod systems add multiple failure points in series with valve operation. Basic reliability engineering shows this is a dumb idea because it reduces system reliability .

In series reliability is the mathematical product of individual series elements. Try multiplying 0.9 time 0.9 and see what you get.

Not to mention the risk of a miss timed switching event causing high enough loads to induce spalling on the lifter roller element.

 

[AEHaas]

"( not to mention there is plenty of research showing thinner oils can reduce ring seal)"

There are studies, from Shell, if I remember correctly, that thinner oils actually result in a better ring seal and more HP.

ali

 

[DuraYuk]

Stribeck curve

Lubrication Fundamentals

www.stle.org

Sommerfeld number and journal eccentricity

https://rotorlab.tamu.edu/me626/Notes_pdf/Notes04%20Static%20Load%20JBs%2010.pdf

There are a half dozen articles from sae describing development of 0w20. You can find those yourself.

Spoiler alert: all of the research was done for fuel economy.

Getting cute with oil viscosity to save 1 mpg is only bargaining with safety factor in the journal bearings.

( not to mention there is plenty of research showing thinner oils can reduce ring seal)

one little blip in polishing or manufacturing and **** here we are.

You’ll note that one of the countermeasures is changing to 0w40.

Secondly, dod systems add multiple failure points in series with valve operation. Basic reliability engineering shows this is a dumb idea because it reduces system reliability .

In series reliability is the mathematical product of individual series elements. Try multiplying 0.9 time 0.9 and see what you get.

Not to mention the risk of a miss timed switching event causing high enough loads to induce spalling on the lifter roller

Again nothing you posted supports your claims.

You are trying to base wear on a malfunctioning engine. That makes no sense.

0w-20 is what the motors were designed for and you just backtracked because at first you said the 6.2 wasnt designed for this.

Now your latching onto 0w 40. That switch isnt for good. Its to take the gap until the engine can be fixed. The new engines still run 0w 20. So if 40 is so good why not just stay there ?

You are assuming a lot of things. First and foremost is idk that you even know what 0w-20 means. Like we are magically assuming its less protection lol.

What Is 0W-20 Engine Oil? | Castrol® USA

What is 0w20 viscosity motor oil & what kind of cars is it used for? What do the numbers mean & is 0w20 full synthetic oil? Learn more here!

www.castrol.com

Why use low viscosity 0W-20 synthetic oil? | Performance Motor Oil & Transmission Fluid | ENEOS

Low viscosity oil, such as 0W-20 synthetic oil, is becoming increasingly popular among vehicle manufacturers.

www.eneos.us

 

[blanchard7684]

Again nothing you posted supports your claims.

You are trying to base wear on a malfunctioning engine. That makes no sense.

0w-20 is what the motors were designed for and you just backtracked because at first you said the 6.2 wasnt designed for this.

Now your latching onto 0w 40. That switch isnt for good. Its to take the gap until the engine can be fixed. The new engines still run 0w 20. So if 40 is so good why not just stay there ?

You are assuming a lot of things.

Literally everything I posted supports the claim. Every single thing. You know the engineering you so dearly profess to love…

The fact that you are summarily dismissing this shows your total ignorance and lack of ability in this discussion.

Just because you type something doesn’t make it so.

 

[DuraYuk]

Literally everything I posted supports the claim. Every single thing. You know the engineering you so dearly profess to love…

The fact that you are summarily dismissing this shows your total ignorance and lack of ability in this discussion.

Just because you type something doesn’t make it so.

I am just a mechatronics engineer im sorry im not a rock star like you. I understand but your basing your finding on an assumption.

And no what you posted does not support your conclusions. Because again you are assuming.

Everything you are posting is an assumption. Without taking into consideration the design parameters which is the most crucial part.

You are not arguing in good faith. You causally ignore the millions of engines that run 0w-20 just fine. The 6.2 is not a complex engine by a long shot. Its not special.

Hey guys run tractor oil because there could be a imperfection! You see how stupid that sounds ? That you are basing your 'finding' on imperfections being present when there shouldn't be!

You gotta be trolling at this point lol. Or this is just way above your head.

 

[WalleyeMikeIII]

@blanchard7684 and @DuraYuk Could you maybe start a thread separate from this one to have a conversation on the pros/cons of 0-20 vs. something else? It is probably a good discussion to have, but is really only tangentially relevant to this 6.2 Recall discussion.

The facts, as we know them are this:
- CrankShafts were improperly machined (Manufacturer admitted as much) for a long window of time.
- Not ALL of them are out of tolerance, manufacturer claims 3%, time will tell on how many it really is.
- Lake Speed was on record saying that he did a lot of work w/ an manufacturer to prove 0-20 would be ok. He said it is, if the surface is smooth enough.
- Thicker Oil, (lets say 0W40) will help if the surface machining is more rough (according to Lake).
- GM is proposing 0W40 as a countermeasure for engines w/ CrankShafts machined out of tolerance that are passing the picoscope test "listening" for bad bearings. It probably does help if the surface is not smooth enough for 0-20.
- The 0-40 Oil may not help if the machining is such that the journals are too big by some amount (This could be the case for that engine Eric tore down see post 1157)

I think none of us have enough engineering data (because GM has not released it) to know for sure whether some, most, or all of these mis-manufactured L87's will fail. GM and their engineers do.

My guess is, properly manufactured crankshafts and bearings are completely fine with 0-20. You can argue all day if it was for fuel economy or not. But hey, if properly engineered and built, it is reliable AND gets higher economy; then yes, we should all want that.

 

[DuraYuk]

@blanchard7684 and @DuraYuk Could you maybe start a thread separate from this one to have a conversation on the pros/cons of 0-20 vs. something else? It is probably a good discussion to have, but is really only tangentially relevant to this 6.2 Recall discussion.

The facts, as we know them are this:
- CrankShafts were improperly machined (Manufacturer admitted as much) for a long window of time.
- Not ALL of them are out of tolerance, manufacturer claims 3%, time will tell on how many it really is.
- Lake Speed was on record saying that he did a lot of work w/ an manufacturer to prove 0-20 would be ok. He said it is, if the surface is smooth enough.
- Thicker Oil, (lets say 0W40) will help if the surface machining is more rough (according to Lake).
- GM is proposing 0W40 as a countermeasure for engines w/ CrankShafts machined out of tolerance that are passing the picoscope test "listening" for bad bearings. It probably does help if the surface is not smooth enough for 0-20.
- The 0-40 Oil may not help if the machining is such that the journals are too big by some amount (This could be the case for that engine Eric tore down see post 1157)

I think none of us have enough engineering data (because GM has not released it) to know for sure whether some, most, or all of these mis-manufactured L87's will fail. GM and their engineers do.

My guess is, properly manufactured crankshafts and bearings are completely fine with 0-20. You can argue all day if it was for fuel economy or not. But hey, if properly engineered and built, it is reliable AND gets higher economy; then yes, we should all want that.

Im with you.

 

[Vladimir2306]

@blanchard7684 and @DuraYuk Could you maybe start a thread separate from this one to have a conversation on the pros/cons of 0-20 vs. something else? It is probably a good discussion to have, but is really only tangentially relevant to this 6.2 Recall discussion.

The facts, as we know them are this:
- CrankShafts were improperly machined (Manufacturer admitted as much) for a long window of time.
- Not ALL of them are out of tolerance, manufacturer claims 3%, time will tell on how many it really is.
- Lake Speed was on record saying that he did a lot of work w/ an manufacturer to prove 0-20 would be ok. He said it is, if the surface is smooth enough.
- Thicker Oil, (lets say 0W40) will help if the surface machining is more rough (according to Lake).
- GM is proposing 0W40 as a countermeasure for engines w/ CrankShafts machined out of tolerance that are passing the picoscope test "listening" for bad bearings. It probably does help if the surface is not smooth enough for 0-20.
- The 0-40 Oil may not help if the machining is such that the journals are too big by some amount (This could be the case for that engine Eric tore down see post 1157)

I think none of us have enough engineering data (because GM has not released it) to know for sure whether some, most, or all of these mis-manufactured L87's will fail. GM and their engineers do.

My guess is, properly manufactured crankshafts and bearings are completely fine with 0-20. You can argue all day if it was for fuel economy or not. But hey, if properly engineered and built, it is reliable AND gets higher economy; then yes, we should all want that.

That's right. I've been trying to prove for a long time that 0-20 oil is not to blame for what's happening to L87.

 

[blanchard7684]

I am just a mechatronics engineer im sorry im not a rock star like you. I understand but your basing your finding on an assumption.

And no what you posted does not support your conclusions. Because again you are assuming.

Everything you are posting is an assumption. Without taking into consideration the design parameters which is the most crucial part.

You are not arguing in good faith. You causally ignore the millions of engines that run 0w-20 just fine. The 6.2 is not a complex engine by a long shot. Its not special.

Hey guys run tractor oil because there could be a imperfection! You see how stupid that sounds ? That you are basing your 'finding' on imperfections being present when there shouldn't be!

You gotta be trolling at this point lol. Or this is just way above your head.

There is no assumptions.

Look up the word before you use it.

If you look at the links and subjects I posted you will see that reducing viscosity does nothing for supporting the proper eccentricity ratio of a bearing.

The dimensions of the bearing are set or fixed since the LS days. Therefore the only parameter changing is load and viscosity.

Lowering viscosity increases eccentricity ratio.

The limit of this is a ratio of 1 which is technically metal to metal contact.

This is not an assumption.

You are conflating a logical deduction with an assumption.

 

[Fless]

@blanchard7684 and @DuraYuk Could you maybe start a thread separate from this one to have a conversation on the pros/cons of 0-20 vs. something else? It is probably a good discussion to have, but is really only tangentially relevant to this 6.2 Recall discussion.

Better yet, a Private Discussion.

 

[Marky Dissod]

... been trying to prove for a long time that 0W20 oil is not to blame for what's happening to L87s.

GM is to blame for what they did / failed to do to several hundred thousand L87s.
Been carrying an 8lb plate of steel in my backpack since I was 14.
Never been back-shot / backstabbed, so the plate gets no credit,
but it's nice to have it there, and you never really know, do you?

If you prefer 0W20, just be aware that 0W40 gives some more protection, that's all.
If you don't need / want that extra protection, ok then.

Y'all need to figure out how to get more of your L87s repaired / replaced.
Focus on THAT.

 

[DuraYuk]

Better yet, a Private Discussion.

I will disengage. Its not going anywhere.

 

[Vladimir2306]

GM is to blame for what they did / failed to do to several hundred thousand L87s.
Been carrying an 8lb plate of steel in my backpack since I was 14.
Never been back-shot / backstabbed, so the plate gets no credit,
but it's nice to have it there, and you never really know, do you?

If you prefer 0W20, just be aware that 0W40 gives some more protection, that's all.
If you don't need / want that extra protection, ok then.

Y'all need to figure out how to get more of your L87s repaired / replaced.
Focus on THAT.

I have already repaired my L87, moreover, I was supplied with a new L87, which was taken out of the box and remade to meet GM standards, which GM itself does not fulfill. And this is not the first time I've heard this about the best 0-40 protection, it is of course better, for engines that are designed for 0-40 oil, if you pour 0-20 into it, it will pour from all the cracks, and when you put 0-20 oil in the engine, you pour thicker oil, it simply does not do its job, because it does not fit where 0-20 will fit and as quickly as 0-20.
But my new l87, due to the correct assembly, has a higher oil pressure by both 0-20 and 0-40.

 

[tagexpcom]

My 2021 Yukon 6.2L has 61K - my VIN comes up on the recall with "no remedy yet".

My question.... is an engine with high mileage more likely OK/in-95%-good-group since it's run smoothly this many miles? OR are do the recall defects run a range of 'a little bad - failure at 90K' to 'worst bad - failure at 2K'.

I think @Vladimir2306 failure was 70K?

Anyone have a sense or data on the range of severity of the defect that's causing the recall? Is there a mileage point where it's clearly not damaged at manufacture?

 

[Vladimir2306]

My 2021 Yukon 6.2L has 61K - my VIN comes up on the recall with "no remedy yet".

My question.... is an engine with high mileage more likely OK/in-95%-good-group since it's run smoothly this many miles? OR are do the recall defects run a range of 'a little bad - failure at 90K' to 'worst bad - failure at 2K'.

Anyone have a sense or data on the range of severity of the defect that's causing the recall? I think @Vladimir2306 failure was 70K? miles.

We also thought that most engines fail at 50-20,000 miles. But unfortunately, we began to have engine breakdowns at 40,000 miles or more, and my engine died at 70,000 miles. The peculiarity of such cars with high mileage, including mine, is a lot of highway trips. Cars that work mainly in the city break down earlier

 

[jfoj]

The facts, as we know them are this:
- CrankShafts were improperly machined (Manufacturer admitted as much) for a long window of time.
- Not ALL of them are out of tolerance, manufacturer claims 3%, time will tell on how many it really is.

@WalleyeMikeIII

Could you please get the facts correct about the number of crankshafts GM "claims are out of tolerance"

First I do not believe GM has ever made a claim or statement about the number of crankshafts that were not machined correctly or out of tolerance. This is because this is a much larger number than they want to fess up about.

The NHTSA document 25C-274 states

"Population: Number of potentially involved : 597,63
Estimated percentage with defect : 3 %'

Understand that this estimated percentage with the defect was based on vehicle having engines fail that caused a lack of propulsion. And I would guess GM was able to make this number look as small as they could with a straight face. This is probably only engines that failed under Warranty and probably only within the US. There are a number of these engines that have failed outside of the warranty window and outside of the US that more than likely are not factored into the "count".

There are credible reports of 28,000-30,000 6.2l l87 engines that have had to been replaced. So this is more closer to 5-6% of the overall vehicle population.

You can choose to believe what you want, but this is a larger problem that GM "claims". They are not going to volunteer any more information than they are required and like any large corporation they will "spin" the story in a way that is favorable for them.

I mean GM has apparently had 3-4 internal investigations and at least 2 other internal Customer Satisfaction bulletins about these problems and it was not until the heat was brought on by the NHTSA that some level of deep investigation seemed to uncover the root cause of 3 years of problems with this engine.

None of us will ever know the entire story or the full percentage of failures, but do not kid yourself that GM is really telling the full truth about this problem.

The Drive - GM Engine Failures