BREAKING: GM is officially recalling the L87

[KMeloney]

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

When I called a local dealer about the recall, the service guy made a comment about there being dirt/contamination in the production process of the metal of these engine parts [that is causing the failures]. Now, I don't know if that's his interpretation of the terms used in the bulletin(s), or whether he got that info on good authority. Well prior to the recall coming out, though, when he had 3 trucks at the dealership waiting for new engines, he said that the failures were due to [a run of] poorly manufactured parts. To me, that checks out/is the culprit here.

 

[jfoj]

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

Big difference, AFM vs DFM and mostly 8 speed transmission.

 

[KMeloney]

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

Exactly. I'm not a soccer mom, and I have only a 10-minute commute to work. The ideas that I shouldn't be warming up the truck before I get in it to drive to work/anywhere, and that I shouldn't drive it for only 10 minutes may be decent preventive measures toward staving off engine failure, but you can't convince me that these (and all engines, really) were designed to NOT be warmed up first, and to ONLY be driven more than 20 minutes at a time.

I think the evidence is pointing to a run of engines built with a run of faulty parts.

 

[Vladimir2306]

Big difference, AFM vs DFM and mostly 8 speed transmission.

It doesn't matter, afm/dfm works on the highway, and in your example about footballers' mothers and short trips to school from home, afm/dfm doesn't work

 

[GMCChevy]

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.

I would guess the failure rate is similar. A large amount of trucks get used for the same sort of driving as full size SUV's. The days of trucks being primarily used for work are long gone.

 

[Marky Dissod]

I think the evidence is pointing to a run of engines built with a run of faulty parts.

This suspicion should always be near the top.
Don't forget that they will also recommend 0W20 instead of 0W30.

Don't see why motor oils that work well in the L8T as well as the LT1 / LT2 / LT4 / LT5
would not work well in other GM 6.2L V8s (not to mention other 5.3L V8s).

 

[Vladimir2306]

I also think that it is a matter of marriage, and not warming up or short trips, especially oil 0-20

 

[jfoj]

It doesn't matter, afm/dfm works on the highway, and in your example about footballers' mothers and short trips to school from home, afm/dfm doesn't work

AFM and DFM does work both on the highway and all conditions. It works even as slow as 20 MPH, I have monitored and you can even hear the changes at the vehicles drive around if you are behind them. You CLEARLY do not understand how AFM/DFM functions.

The difference is DMF can operate on as few as 1 cylinder, AFM operates on as few as 4 cylinders. Seems the MAJORITY if the failures are at highway speed when the DFM is possibly trying to run on as few as 1 to 3 cylinders and is actively dancing around during all of the combinations. Putting all the load on between 1 and a few cylinders.

 

[Lonny]

Just talked to my dealership about my Escalade. According to them, no parts are available right now, no work can be done right now, the dealership cannot do anything right now. They aren't going to do anything for the moment. The guy told me to wait until I receive a letter in the mail with further instructions.

Meanwhile, I've got an alert in the MyCadillac app saying "dealer will inspect and as necessary, repair or replace the engine??!?!!?"

What the hell are we supposed to do?

 

[blanchard7684]

Just talked to my dealership about my Escalade. According to them, no parts are available right now, no work can be done right now, the dealership cannot do anything right now. They aren't going to do anything for the moment. The guy told me to wait until I receive a letter in the mail with further instructions.

Meanwhile, I've got an alert in the MyCadillac app saying "dealer will inspect and as necessary, repair or replace the engine??!?!!?"

What the hell are we supposed to do?

If it were me I'd be doing a 0w40 swap this weekend. It is the easiest thing end user can do to improve their odds against a failure.

 

[jfoj]

I know what I would do!

Take matters into your own hands.

Really nothing more than a free oil change.

If you can DIY, you can probably do the oil change for $50-$70 depending on the oil, pricing and any rebates or discounts.

I go a bit on the higher end, while not "officially" Dexos approved it would pass without any issues. Higher end oil is not usually submitted for certain approvals because the vendors would need to provide the formulation and this is intellectual property many vendors do not want to surrender on their upper level products.

 

[KMeloney]

The difference is DMF can operate on as few as 1 cylinder

Is this true? 1 cylinder? (Not a rhetorical question, btw.) Or is that theoretical? Just seems impossible (or just impossibly stupid) from an engineering standpoint that the truck could be motivated at all on 1 cylinder.

 

[Vladimir2306]

AFM and DFM does work both on the highway and all conditions. It works even as slow as 20 MPH, I have monitored and you can even hear the changes at the vehicles drive around if you are behind them. You CLEARLY do not understand how AFM/DFM functions.

The difference is DMF can operate on as few as 1 cylinder, AFM operates on as few as 4 cylinders. Seems the MAJORITY if the failures are at highway speed when the DFM is possibly trying to run on as few as 1 to 3 cylinders and is actively dancing around during all of the combinations. Putting all the load on between 1 and a few cylinders.

Dfm works not on one cylinder, but on two, or more, and you can't understand how many cylinders are working at the moment)) and the dashboard does not show the number of working cylinders in any way))) so most likely you receive some other sound))

 

[KMeloney]

Just talked to my dealership about my Escalade. According to them, no parts are available right now, no work can be done right now, the dealership cannot do anything right now. They aren't going to do anything for the moment. The guy told me to wait until I receive a letter in the mail with further instructions.

Meanwhile, I've got an alert in the MyCadillac app saying "dealer will inspect and as necessary, repair or replace the engine??!?!!?"

What the hell are we supposed to do?

I got the same exact response from my service manager -- but with the addition of the belief that they're going to be told by GM to just replace the engines on the list.

 

[Vladimir2306]

Is this true? 1 cylinder? (Not a rhetorical question, btw.) Or is that theoretical? Just seems impossible (or just impossibly stupid) from an engineering standpoint that the truck could be motivated at all on 1 cylinder.

No, of course, he says nonsense, dfm does not work on one cylinder)))

 

[jfoj]

Is this true? 1 cylinder? (Not a rhetorical question, btw.) Or is that theoretical? Just seems impossible (or just impossibly stupid) from an engineering standpoint that the truck could be motivated at all on 1 cylinder.

Yup, impossibly stupid just 1 cylinder!! And not just the same 1 cylinder every time, it jumps around, but unclear really how random it could be.

I have also seen reference to running on 2 cylinders.

So you tell me what this means "but DFM actively turns off any number of cylinders in a variety of combinations"

There is not as much information out there about 100% how the DFM operates other than is has like 17 different operation modes.

I do know for sure that under DFCO (Decel with Fuel Cutoff) they do seem to shut all cylinders down with DFM, or at least in some order this does occur because I have watch the cylinder deactivation counts.

DFM Operation

DFM Overview

 

[suburbansince87]

I just replaced the oil in my wife's '22 6.2L over the weekend... with 0W-20. Wish I had kept up with this forum

 

[DontTaseMeBro]

I just replaced the oil in my wife's '22 6.2L over the weekend... with 0W-20. Wish I had kept up with this forum

You'll be fine. Just don't put more than 3k miles on it.

 

[Vladimir2306]

Yup, impossibly stupid just 1 cylinder!! And not just the same 1 cylinder every time, it jumps around, but unclear really how random it could be.

I have also seen reference to running on 2 cylinders.

So you tell me what this means "but DFM actively turns off any number of cylinders in a variety of combinations"

There is not as much information out there about 100% how the DFM operates other than is has like 17 different operation modes.

I do know for sure that under DFCO (Decel with Fuel Cutoff) they do seem to shut all cylinders down with DFM, or at least in some order this does occur because I have watch the cylinder deactivation counts.

DFM Operation

DFM Overview

By the way, where did you get the information about the constant load on the engine in the city of 70-80%? Here is the load schedule, I am now driving around the city in the mode of 10-20-30 miles per hour. 70% is the peak when I accelerated a little, and so the average load is 25-30%
When you release the gas pedal, the engine stops supplying fuel to the cylinders at all, haha, you confuse DFM work with forced idling, or this is known as coasting. This was done on carburetor engines)))

 

[Marky Dissod]

DFM has V8, V7, V6, V5, V4, V3, V2, I2, & 0-cylinder modes.
Total of seventeen different possible firing orders, constantly changing.
The exact same firing order is never consecutively repeated.

Each cylinder's duty cycle is kept as close as possible to identical to each other,
compared to Engine Half@$$, basically a part-time V4 sharing a crank with a fulltime V4.