BREAKING: GM is officially recalling the L87

[DuraYuk]

Yeah it's not the oil. It's a band aide like I thought.

https://gmauthority.com/blog/2025/04/heres-why-gm-6-2l-v8-recall-doesnt-apply-to-2025-model-year-vehicles/

 

[jfoj]

It will be interesting to watch if this "Recall" is based fully on model years or if it is narrowed down to engine build date based on "A series of crankshaft and connecting rod manufacturing improvements implemented on or before June 1st, 2024, addressed contamination and quality issues". To me this a bit too vague and it really does not fully address what was wrong and what changed, but we many never know.

I have a 2024 GMC Yukon with a production month of 8/2024, my engine build date is July 15, 2024 based on the Julian date of the engine production tag so in theory my engine was built after the manufacturing improvement date with my 2024 model. So far I have not found that my VIN has been recalled, however, I also believe that the databases have not been fully populated and the official NHTSA Recall Notice 25V274 has not been release yet. There seems to typically be a slight lag for the official NHTSA notices as I see about 4 that have been assigned a 25V27** number since 4/23/2025 that do not have supporting documentation released on the NHTSA page yet.

I guess we shall see what the final recall window looks like and we will need to see if there are any/many 6.2l failures beyond the June 1, 2024 engine build date. I assume there is typically at least a 2-3 week delay time between the build date of the engine and the build date/month of the vehicle. So this should mean that any 7/2024 and newer builds with the 6.2l would somehow have benefitted from the "manufacturing improvements".

When I went looking for my Yukon, I want as late a build date on the vehicle as possible in case there were any running changes. Maybe I was wise?? Who knows.

We shall see.

 

[blanchard7684]

Yeah it's not the oil. It's a band aide like I thought.

https://gmauthority.com/blog/2025/0...-doesnt-apply-to-2025-model-year-vehicles/[/U

Starting to agree...

 

[Vladimir2306]

Yeah it's not the oil. It's a band aide like I thought.

https://gmauthority.com/blog/2025/04/heres-why-gm-6-2l-v8-recall-doesnt-apply-to-2025-model-year-vehicles/

Of course, this is not oil, and not the operating conditions, and not connecting rod bearings, because their part numbers have not changed, as they have not changed on the models of the 25th year, as well as on the 24th year. And it's not gasoline in the oil, or warming up the engine.I am more than sure that there was a banal defect in the production of engines, which has now been corrected, without changing the operating conditions, and without changing the oil and spare parts.I told them how the engines arrived, new, in a box, they were opened, and their temperature gaps were violated. The piston on the new engine did not move freely, it was wedged.
and switching to 0-40 oil is just to get the engines to the end of the warranty period.

 

[GMCChevy]

Those are good discussion points.

When an engine, or specifically a rotor system with hydrodynamic bearings, is designed with 0w20 as the primary oil then it can work. If you set your viscosity to a 0w-20, then design the bearing width, diameter, and clearance to support a good eccentricity ratio, then it will work. further, you can even see how low the viscosity can drop before the eccentricity ratio gets into a danger zone.

Victor Sheppard took 2 toyota engines to 1 million miles using 0w20 and 10,000 mile oil change intervals.

Louisiana Man Puts 1 Million Miles on a Toyota Tundra—for the Second Time

Longtime Toyota truck owner Victor Shepherd drives an average of 10,000 miles a month.

www.thedrive.com

And yeah lots of highway miles but hot shot drivers also get a lot of idling time waiting to be loaded up...

Toyota's V35A-FTS recall on the new 3rd gen was, according to them, debris related. It wasn't every single v6 either-- the Lexus GX 550 wasn't in the recall despite having same basic engine (different turbo and induction system).

Looking at the failed bearings it didn't look like debris was the issue. And how debris "shows up" as a failure in trucks with 46,000 (or more) miles is a painful stretch of credibility. I'm sure debris was an issue but not the whole story.

The failed bearings appeared to show an overload condition from too little clearance: a shifting main cap ("cap walk" on forced induction engines is a thing) or the main cap jaw fits being too tight or too loose. The main bearing cap design and the main cap girdle/web stiffener was changed from original 2018 Lexus design.

Could 0w20, especially a fuel diluted oil, be a major contributor? sure. But the original V35A never had the bearing problem even using 0w20 which it was designed for. And I'm sure there were plenty of lazy LS 500 owners who justified 10,000 mile oci's while taking short trips and idling extensively outside of Whole Foods...meaning plenty of cases of fuel diluted engine oils...

The problem popped up when the main cap and girdle design changed.

And it is known that the GX 550 has a different main bearing part number than what is in Tundra or Lexus LX600. The GX 550 never had this issue.

Regardless...Toyota stomped that problem out fast and it didn't involve changing oil spec.

The bottom end of the 6.2 and 5.3 haven't materially changed since their inception as an LS1 engine. But what has changed is getting cute with 0w20.

If an engine was designed originally for 0w20 you can be reasonably sure it is good to go. If an engine was designed for a higher viscosity oil and suddenly, and with no clear design change to support it, drops the viscosity down a few grades, while increasing specific power output from engine, then red flags should be going up.

At the same time these engines have been using 0W-20 since around 2013 without major issues until the last few years with the 6.2 and now there are people who even have failures within a short amount of time of getting a warranty engine. That's a huge sign there's something else going on.

 

[jfoj]

Based on this article below from a bearing manufacturer, loose bearing clearance require/benefit from a higher viscosity oil. But I am still convinced that fuel contamination is a major factor in many of these engine failures, thinning out the engine oil over the lifetime it is in the engine.

So if GM has wholesale stated that close to 1 Million engines that were spec'ed and supposedly designed for 0W20 engine oil should now run 0W40 engine oil, this tells me that GM must have decided that the engine bearing clearances were too loose or they feel that premature wear (loosening of the bearing clearances) has occurred and that higher viscosity oil will allow the engine to last longer.

UNDERSTANDING OIL CLEARANCES IN ENGINE BEARINGS - Engine Builder Magazine

One way to make engines live and have good durability is to have just the right amount of bearing oil clearance. Maintaining a cushion of oil between the bearing and shaft is essential for proper bearing operation and to prevent metal-to-metal contact. Generally, tighter oil clearances are...

www.enginebuildermag.com

 

[Vladimir2306]

Based on this article below from a bearing manufacturer, loose bearing clearance require/benefit from a higher viscosity oil. But I am still convinced that fuel contamination is a major factor in many of these engine failures, thinning out the engine oil over the lifetime it is in the engine.

So if GM has wholesale stated that close to 1 Million engines that were spec'ed and supposedly designed for 0W20 engine oil should now run 0W40 engine oil, this tells me that GM must have decided that the engine bearing clearances were too loose or they feel that premature wear (loosening of the bearing clearances) has occurred and that higher viscosity oil will allow the engine to last longer.

UNDERSTANDING OIL CLEARANCES IN ENGINE BEARINGS - Engine Builder Magazine

One way to make engines live and have good durability is to have just the right amount of bearing oil clearance. Maintaining a cushion of oil between the bearing and shaft is essential for proper bearing operation and to prevent metal-to-metal contact. Generally, tighter oil clearances are...

www.enginebuildermag.com

and 0-40 oil means it doesn't dilute the fuel? Lol. GM chose 0-40 oil to simply choose the lesser of two evils, that's all. 0-40 oil makes the engine suffer after 70-80-100 thousand miles, but the problem with connecting rod bearings won't appear after 1000 miles, that's all

 

[jfoj]

0W40 will also become fuel diluted just like 0W20, it just has a far bigger safety margin, before the viscosity gets equal or below the viscosity of fresh 0W20 oil.

Again, it has a lot to do with how the vehicle is used. Too many Soccer Moms running too many short trips in the colder months and even the warmer months, but the Soccer Mom mobile maybe gets enough miles for a single oil change a year. If I would have run my kids to school they are all within 1-2.5 miles from my house. So just think about how this would impact any vehicle much less something like these trucks that take 30 minutes of driving for the oil to fully warm up.

Far different than most trucks that actually get worked and have miles put them. Some trucks are play toys, many are working trucks.

I would love to see the distribution of engine failures of SUV's vs Pickups. My gut tells me based on reports I have read is probably around 4-5 SUV to pickup, but this is my gut based on reports I have read. Maybe the distribution is equal to the number of SUV to Truck sales? Who knows.

 

[blanchard7684]

At the same time these engines have been using 0W-20 since around 2013 without major issues until the last few years with the 6.2 and now there are people who even have failures within a short amount of time of getting a warranty engine. That's a huge sign there's something else going on.

Agreed. There is probably a whole lot more to the manufacturing defect story than is currently known outside of GM technical staff.

My guess is some sort of tolerance stacking. The right combination of parts that are at their spec limits can cause a failure in the right conditions: diluted oil, low on oil, high loads and low rpms. Thus changing the oil to 0W40 mitigates this substantially.

The problem with the oil spec change is that if you already have some minor damage incurred, and it takes a few more cycles to develop into a failure, 0w40 isn't going to help much--you need new parts that are actually in spec.

If you start out fresh or low miles with 0w40 you'll likely miss the failure mode. Still a band-aid though--what you need is in spec batch of parts. That is actually what you paid for.

 

[Vladimir2306]

0W40 will also become fuel diluted just like 0W20, it just has a far bigger safety margin, before the viscosity gets equal or below the viscosity of fresh 0W20 oil.

Again, it has a lot to do with how the vehicle is used. Too many Soccer Moms running too many short trips in the colder months and even the warmer months, but the Soccer Mom mobile maybe gets enough miles for a single oil change a year. If I would have run my kids to school they are all within 1-2.5 miles from my house. So just think about how this would impact any vehicle much less something like these trucks that take 30 minutes of driving for the oil to fully warm up.

Far different than most trucks that actually get worked and have miles put them. Some trucks are play toys, many are working trucks.

I would love to see the distribution of engine failures of SUV's vs Pickups. My gut tells me based on reports I have read is probably around 4-5 SUV to pickup, but this is my gut based on reports I have read. Maybe the distribution is equal to the number of SUV to Truck sales? Who knows.

And there were no mothers of football players on K2 with a 6.2 engine and 0-20 oil, or did they drive differently before? Or maybe the fuel was different, which was less irritating to the oil