New bulletin/Campaign 6.2 L87

[brianf60]

8 hours ago, newdude said:

 

Their method seems to be an ok approach here.  Why just shotgun BILLIONS of dollars into replacing 700,000 engines right out of the gate if not every single one will fail?  They'd be facing bankruptcy over this and or will have a really major cost cutting approach that won't involve cutting CEO salary, rather affect vehicle quality and plant workers and maybe corporate white collars being axed.  And those that pass the test, extend the warranty IF it were to fail down the line.  

 

 

 

The only problem with this approach is what about when the failure leaves someone stranded and out of pocket for thousands in expenses? Like I mentioned earlier the valvebody failed in my wife’s Tahoe when we were 12 hours from home. GM has reimbursed us for some of the expenses but only about half. I’m still out of pocket for 3 nights in a hotel and flights. 
so far they have only paid for my flight back to pick it up. There would need be an assurance that all the vehicle owners failed trip costs are covered. Otherwise GM saves a fortune by not replacing 700,000 engines but the average Joe gets left shouldering the expense of failed part. 

[newdude]

11 hours ago, brianf60 said:

The only problem with this approach is what about when the failure leaves someone stranded and out of pocket for thousands in expenses? Like I mentioned earlier the valvebody failed in my wife’s Tahoe when we were 12 hours from home. GM has reimbursed us for some of the expenses but only about half. I’m still out of pocket for 3 nights in a hotel and flights. 
so far they have only paid for my flight back to pick it up. There would need be an assurance that all the vehicle owners failed trip costs are covered. Otherwise GM saves a fortune by not replacing 700,000 engines but the average Joe gets left shouldering the expense of failed part. 

 

 

Assuming GM will be adding warranty to those that pass (which is still not 100% confirmed) then IF the passed engine had an issue while on 0w40 in the warranty time frame (again if they do actually offer the extended warranty which seems to be something that is going to happen) then it would be a covered engine replacement.

 

Anyone who doesn't like that?  Dump the vehicle.  Trade it, sell it private, whatever.  Dump it.  

[KARNUT]

Time to put down the knives and be realistic. Did someone mess up probably. Should someone had done something earlier, definitely. Pushing too hard can result in chapter 11. Then you can forget about it. Extended the warranty gets most people through the payments or at least right side up. If you can switch with the wife if she’s driving a 6.2. Stay to the extreme right or left and pay attention. That should help most people. The rest can trade in to GM with no penalty. 

Edited May 17, 2025 by KARNUT

[MrLeadFoot]

On 5/16/2025 at 7:57 AM, Byrds8 said:

Nothing that I have noticed. Seems pretty on par IMHO. Granted this is going off the DIC as I stopped hand jamming the numbers a while ago cause I stopped caring lol. I saw more MPG drop from switching from 91 Oct no ethy to 93 Oct with. LOL

I, initially, hand calculated MPG to compare to the DIC and found that the DIC is pretty darned accurate. So, rest assured you can rely on the DIC unless, of course, you changed your wheel diameter. 

 

On another note, believe it or not, I actually get better gas mileage running regular vs. premium which, where I am, is 87 and 91 respectively. I was very surprised and tested it more than once.

 

Regardless, I run premium because I figure that that is what the motor is programmed to run, by default. Right or wrong, I reason that, even though the programming is designed to pull timing (the forum censored the more technical word) to accommodate for lower octane fuel, I believe it does that when it senses knocking. But, that can't be good over the long run, can it? If someone can share why it's OK to drive with a condition that's going to cause knock often, without detrimental effect over the long haul, I'll gladly use 87 regularly, because in my state we're raped by gas prices as it is, and my regular is nearly double what other states pay for premium, and their premium is 93, whereas mine is only 91!

Edited May 17, 2025 by MrLeadFoot

[66ss3964spd]

Not surprised about the mileage increase with 87, 87 burns easier than 89, 91, 93. Under a light load and cool conditions the engine might tolerate a lower octane. 

 

Regardless of the engine it will only achieve its rated HP/TQ by using the octane it was designed for. Pulling timing out to reduce/eliminate knocking is, basically, pulling HP and TQ out.

 

Pre-detonation (knocking) is hard on pistons, rings, wrist pins, and rod bearings. The knock sensors are reactive, not predictive; pre-detonation has to happen first before the sensors hear it and the timing is trimmed.

[Jus Cruisin]

5 hours ago, KARNUT said:

Time to put down the knives and be realistic. Did someone mess up probably. Should someone had done something earlier, definitely. Pushing too hard can result in chapter 11. Then you can forget about it. Extended the warranty gets most people through the payments or at least right side up. If you can switch with the wife if she’s driving a 6.2. Stay to the extreme right or left and pay attention. That should help most people. The rest can trade in to GM with no penalty. 

Personally, I wasn't afraid of being stranded (a low percentage will actually fail) and I've had a couple of engines blow up driving during my nearly 60 years with a license. Try having an engine go south out in Podunk before cell phones were invented.

 

My problem was the replacement delay and because of that I have a twin to my 2023 except for the engine. Traded yesterday. 

Edited May 17, 2025 by Jus Cruisin

[MrLeadFoot]

11 hours ago, 66ss3964spd said:

Not surprised about the mileage increase with 87, 87 burns easier than 89, 91, 93. Under a light load and cool conditions the engine might tolerate a lower octane. 

 

Regardless of the engine it will only achieve its rated HP/TQ by using the octane it was designed for. Pulling timing out to reduce/eliminate knocking is, basically, pulling HP and TQ out.

 

Pre-detonation (knocking) is hard on pistons, rings, wrist pins, and rod bearings. The knock sensors are reactive, not predictive; pre-detonation has to happen first before the sensors hear it and the timing is trimmed.

 

11 hours ago, 66ss3964spd said:

 

So, it sounds like you're saying I'm correct in that it's not good to run 87 because it has to knock before it pulls timing, and each time it knocks it's bad for the engine, is that correct? 

 

FWIW, I don't need max hp or torque very often, especially since these motors are beasts already but, even if one drives it "normally", isn't the effect of using 87 still detrimental, or is the programming designed so that timing does not increase until you romp on it (and that increased timing is regulated and pulled when necessary), so it will not pre-detonate on 87 when driving "normally"?

Edited May 18, 2025 by MrLeadFoot

[66ss3964spd]

9 hours ago, MrLeadFoot said:

So, it sounds like you're saying I'm correct in that it's not good to run 87 because it has to knock before it pulls timing, and each time it knocks it's bad for the engine, is that correct? 

That's what I'm suggesting.

 

BTW, I said "pre-detonate", which is kind of incorrect. Should just be "detonate". 

 

I doubt the ECU has any provision to determine what octane is being used so it is only going off what the knock sensors are telling it. Soon as a sensor hears the ping, or several pings, the ECU retards the timing then at some point restores the timing if the pinging has stopped. It always wants to run as much advance timing as it can (up to its designed max) to extract max power and fuel mileage.

 

There are a LOT of variables in play; static compression ratio, dynamic compression ratio (partially influenced by camshaft design), coolant temp, air temp, air density, fuel delivery timing and quantity, engine load, RPM. Probably others. Some you can control with your right foot, others you can't.

9 hours ago, MrLeadFoot said:

I don't need max hp or torque very often

Most people don't. But when you do, you do, and often you can't predict, or control the circumstances, when you do.

 

Given that the rod and main bearings have been identified as a bit of a problem in the 6.2 under normal operation, I wouldn't want to knowingly induce any abnormal (knocking) operation that could possibly make matters worse.

[MrLeadFoot]

9 minutes ago, 66ss3964spd said:

BTW, I said "pre-detonate", which is kind of incorrect. Should just be "detonate". 

That's funny, because I went with your term, too, without realizing that we both meant to say "pre-ignition", but hey, if there is any silver lining in all the madness of this record-setting recall in automotive history, it's that you created a new hybrid word, and I solidified it's place in history by using it after you! 

[66ss3964spd]

Pre-ignition and detonation are often used interchangeably but are not, technically, the same thing. But they both have the same adverse effects.

[MrLeadFoot]

13 minutes ago, 66ss3964spd said:

Pre-ignition and detonation are often used interchangeably but are not, technically, the same thing. But they both have the same adverse effects.

I am guilty of this, and stand corrected. I always thought they were the same thing, but see now that detonation is the correct term for the low octane ping we were talking about. I also apologize for putting words in your mouth, too. 

Edited May 18, 2025 by MrLeadFoot

[66ss3964spd]

No worries, my wife would confirm that I sometimes just make words up!

[MrLeadFoot]

10 minutes ago, 66ss3964spd said:

No worries, my wife would confirm that I sometimes just make words up!

That's funny!

 

As to the new hybrid word, "pre-detonation" is actually an oxymoron, and might be useful to confuse knowledgeable folks in the right setting (like after a couple of drinks). 

[GullLakeMi]

On 5/15/2025 at 8:58 PM, Andrew Martens said:

Just got my truck back from the dealer. They did install all new injectors and they had to re-seal the oil pan. Said that the silicone at the rear of the engine was too thinly applied. They put on about 60 miles test driving it, then they took pictures and it does look dry now. 

Also, I was told that what they call “service”  replacement engines are remanufactured and NOT brand new. So only factory assembly line vehicles get new engines. 

How many of those can they have sitting around?  Think they took your original, swapped parts and will give it to the next guy?

[customboss]

https://www.sae.org/news/2025/05/2025-ford-expedition-and-tremor-first-drive

 

2025 TREMOR EXPEDITION an option for not having leaving you DOR with GM ? 

 

I'm not a FORD guy but this looks solid in off road work. 

 

 

 

Edited May 19, 2025 by customboss