BREAKING: GM is officially recalling the L87

[OR VietVet]

Yea, same company I use. I had a specific problem and he called me and I texted back with answers and now have his personal phone number. Cool guy and great videos at you tube.

 

[CCPLuvr]

This thread has become almost addictive to follow. I probably check it 3 times a day...

 

[CCPLuvr]

Our 2024 AT4 engine code was 10 days outside the affected population. I've switched to Mobil 1 5W-30 and will continue with that for the foreseeable future. I'm curious to see how GM will react to future warranty claims by people who have voluntarily switched to 0W-40 given they published this as part of the fix.

 

[KMeloney]

@Vinmega Only 3% of the 3.2m engines have a defective internal part, the rest are fine.

Remind me where you've seen this 3% figure stated as fact, please.

 

[jfoj]

From the NHTSA 25V274 document

"Population : Number of potentially involved : 597,630 Estimated percentage with defect : 3 %"

ESTIMATED percentage with defect.

I bet the number is much higher than that as GM has no freaking idea over a 4 year period exactly what went wrong and when it went wrong, otherwise there would not be 600,000 vehicles being recalled.

GM Estimates my vehicle is outside of the engine problem window, which GM has adjusted by 1 month at least once so far. Hopefully GM does not move the goal posts again.

 

[jfoj]

Our 2024 AT4 engine code was 10 days outside the affected population. I've switched to Mobil 1 5W-30 and will continue with that for the foreseeable future. I'm curious to see how GM will react to future warranty claims by people who have voluntarily switched to 0W-40 given they published this as part of the fix.

GM claims ONLY engines that are within the specific Recall window for engine DATE will be "Inspected" with for the P0016 codes and they will put a temporary knock sensor on the engine and use a Pico Scope (Digital Storage Oscilloscope Module) and run a test at a specific RPM and engine coolant temperature then the captured waveforms from the knock sensor will be analyzed by DSP/FFT and with then generate a "Pass or Fail" If the test "Fails", new engine. If the test is "Pass" oil change with 0W40 oil, new oil filter, new oil fill cap that has 0W40 printing and an addendum to the owners manual. These engines that "Pass" will get a 10 year/150,000 mile engine warranty extension from the date the vehicle was put into service.

Replacement engines WILL NOT get 0W40, they will continue to use 0W20.

So ONLY the "Pass" engines that are within the questionable engine build window will get 0W40 engine oil.

If you choose to run something other than 0W20 on engines not within the questionable engine build window, this is your choice and mine! 5W30 or 0W40 will not cause the engine to fail, other problems will. The dealership will not likely even know what oil you are running in the engine unless you tell them. But if the crankcase is clean and there is either a bearing, lifter or cam failure, it will not likely be causes by 5W30 or 0W40 oil because those exact oils are recommended in pretty much the same engine platforms in other vehicles.

The question is HOW MANY "Pass" engines with 0W40 will live to 150,000 miles and beyond? Only time will tell.

 

[vcode]

OK here is the first oil analysis I've done on this truck. I use this service on both my race cars and never thought I would need it on the tow vehicle
This sample was from after removing the dealer changed 0w-20 that was put in around 7000 miles during it's "first scheduled service". It came out around 9500 miles after learning about the recall.
I swapped it out for 0w-40 M1. Lake suggested running 2 more changes through it before sending in the next sample (0w-40) to analyze. So I will do this after two 3000 mile intervals. Truck now has about 10.5k on it, so that will be at around 16-18k miles.

Lake says they see that it typically takes 3 to 4 oil changes to finally remove all of the break-in debris and for the wear rate to drop into the normal level. More frequent oil changes early on gets this process completed sooner. So that is the plan to keep the oil pressure up and the blood pressure low.

PS - I have zero affiliation with Lake other than being a happy customer. I particularly appreciate the time he takes to provide answers to specific questions. ymmv.

See his notes at the bottom of the graphic.

View attachment 457606

Pretty much what I would expect at that mileage. Too bad you didn't go 5000 miles, would have been interesting to see.

 

[jfoj]

I am going to monitor the color of my engine oil, but I am thinking that 4,000 mile OCI will be what I plan on using. I want to see what the OLM indicator shows as % around the 4,000 mile mark. I was hoping to keep it simple and just use 50% OLM reference, but need to get some more miles to see what % OLM will be my threshold.

I am thinking that 55-60% OLM indication may be around the 4,000 mile mark based on what I am seeing at this moment.

 

[DuraYuk]

I am going to monitor the color of my engine oil, but I am thinking that 4,000 mile OCI will be what I plan on using. I want to see what the OLM indicator shows as % around the 4,000 mile mark. I was hoping to keep it simple and just use 50% OLM reference, but need to get some more miles to see what % OLM will be my threshold.

I am thinking that 55-60% OLM indication may be around the 4,000 mile mark based on what I am seeing at this moment.

The oil life monitor is dynamic not static. So everyone's % will be different.

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[jfoj]

Understand but was looking for a reasonable and somewhat repeatable value that I could use other than straight mileage base. About 80% of my driving is highway at this point.

It is just kind of interesting that almost all the CPO units I looked at also has 7500 mile oil changes. And I was notified by My GMC App that I have a 7500 mile milestone service as well. Maybe these OLM will run past 8,000 in many cases???