UOA and Filter photos of L87 time bomb.

[apex944]

Let me tell you an L87 story, with documented evidence of how bad these engines are.
My 2024 Yukon Denali is just over 2 years old with 20k miles on it. Passed the Pico Test at its first post-recall service.
At that time the oil was changed to 0w-40 and got the new cap.

2500 miles later I changed the oil and filter again and did a UOA with Lake Speed.
The UOA show elevated levels of Silicon and wear metals. Not absolutely outside the possibility that it was still breaking in.
So we carried on, and in another 2500 miles I changed the oil and filter for the 3rd time. No UOA this time.

Just last week we took a long trip and upon my return, with nearly 20k on the clock, I decided to do another oil change and send a sample off to Lake again.
Upon receiving the results of this UOA I was very disapointed to see the total wear metals still increasing.

As a result I decided to cut open the filter. I found considerable bearing material in the pleats.
At 20,000 miles after 4 changes, this engine should be clean and free of any metal.

Attached are the UOA and a filter pic. The closer side of the filter is the side full of swarf. The farther sided is the outside where there is none.
The difference is clear.

This engine is going to fail, yet the dealer says it passed and is "good to go"
I am now looking for an Expedition.

PS - I just found out a buddy picked up a used, tested and approved Denali exactly like mine. HE drove it 500 miles and the engine seized up on the highway.

 

[PPK_]

I am not sure why the gm pico test is at 2k rpm. I think you should look at idle, 2k and then run it up and down in rpm looking for some clearance… i am an engineer.. what do i know? At 2k rpm.. oil pressure is high. You won’t find much clearance issues..

I had a vibration sensor on my 5.3 motor. The v8 has some forces from the left bank.. some from the right side.. these are at 90 deg angles.. i did not see anything looking at x,y and z axis…

And i have just a little on my mag drain.

Your engine.. does not look good. Bummer

 

[West 1]

Take the oil reports to your GM dealer, ask for your new engine and enjoy the car after repair. With all the new parts that come with a new engine you are coming out ahead on the deal. Why stress over it. If you like the vehicle get it fixed while it is fully covered.

 

[blanchard7684]

The dirt/silicon readings are really standing out. With 20,000 miles that should be minimal and well below 20 ppm.

The iron readings are also unexpectedly high given the typical way the engines fail.

And I would agree that the oil analysis suggest incipient failure of some sort is occuring.

 

[Stbentoak]

You can pile up all the evidence you want. The only thing the dealer is going to say is run until it breaks. The $60 question is when's it going to break? In your driveway or on I-75 at 83 miles an hour on your way to Disney World.......

 

[apex944]

Why stress over it. If you like the vehicle.

Assumption 1: I'm not stressed.
Assumption 2: Dealer is not going to give a new engine.

Do I like the vehicle? Well ... about that...
Setting the engine aside for a moment. I have the air suspension. There is zero damping.. none. The "shocks" feel liek they are blown. It clunks over every bump or sharp rise on the road. It rolls like there is no rebound damping when you go in and out of driveways...actually bangs my wifes head off the side glass. Dealer said "they are all like that". I doubt this.

Then there is the transmission. Poor programming. Even in L9 its constantly shifting at inaapropriate times. I cant pull away from a stop with very light throttle without it jerking my passengers around as it shifts. For $90k this shoudl be fluid and flawless. It's just garbage.

The leather interior is very nice.

And back to the enigine.. let's pretend mine wasn't machining itself ... the enigne is not smooth at idle. It's more noisy and has more vibrations than a modern V8 should. It hesitates and doesnt pull smoothly awy from stops .. (partially due to trans)

So, not good. A waste of $90k ... I will either go with a Duramax and a std suspension or an Expedition. I'd love a Sequoia but they made the back useless with the battery pack.

 

[jfoj]

Apex, check your messages

 

[LEsoftballdad]

I recently replaced my Yukon with an Expedition. Here's what they both did well, and what I don't like.

The Expedition is far more comfortable. The genuine leather in the Platinum Ford is more plush and comfortable on long rides. The Ford I have does not have the CCD, so the ride can be bumpy on uneven surfaces. The 3.5 Ecoboost is a solid power train with plenty of power. It can get 21 mpg on the highway, if you're not going 75 mph. The tech has been easy to use and learn. Lastly, the steering wheel, which some people hate, is actually quite nice for me.

My Yukon was a 24 with the 3.0 Duramax. It was a good engine with very good mileage, but I never approached 30 unless I was going 50 MPH. What drove me to get rid of it was the fact the seats were not comfortable. Anything more than 45 minutes of driving made my back and hips hurt.

If I could have combined the comfort and tech of the Ford with the efficiency of the LM2 Duramax, I would have been thrilled.

 

[jerry455]

Wow, my 2021 6.2, with 102,000 miles, is smooth. It pulls pretty well considering the weight of the truck. I don't have air ride just the mag ride and it is fantastic. My wife says it is the nicest riding vehicle she has ever been in. I wish the trans would shift with more authority. I like a firmer shift. I have never liked a smooth shift, too much overlap and bad for trans life. I can get 19-20 mpg on the freeway. Around town it is 13-15. I don't really care about fuel economy anymore. I like driving this vehicle and I don't even mind using premium. It has been a good vehicle for the past 30,000 miles or so.

 

[apex944]

Wow, my 2021 6.2, with 102,000 miles, is smooth. It pulls pretty well considering the weight of the truck. I don't have air ride just the mag ride and it is fantastic. My wife says it is the nicest riding vehicle she has ever been in. I wish the trans would shift with more authority. I like a firmer shift. I have never liked a smooth shift, too much overlap and bad for trans life. I can get 19-20 mpg on the freeway. Around town it is 13-15. I don't really care about fuel economy anymore. I like driving this vehicle and I don't even mind using premium. It has been a good vehicle for the past 30,000 miles or so.

Yup. The air suspension is the entire problem. Totally undamped. (I sell race shocks so I have experience with this)

 

[Joseph Garcia]

Wow, my 2021 6.2, with 102,000 miles, is smooth. It pulls pretty well considering the weight of the truck. I don't have air ride just the mag ride and it is fantastic. My wife says it is the nicest riding vehicle she has ever been in. I wish the trans would shift with more authority. I like a firmer shift. I have never liked a smooth shift, too much overlap and bad for trans life. I can get 19-20 mpg on the freeway. Around town it is 13-15. I don't really care about fuel economy anymore. I like driving this vehicle and I don't even mind using premium. It has been a good vehicle for the past 30,000 miles or so.

You should consider getting a tune on your transmission's operation. The shift firmness should be adjustable to your liking.

 

[West 1]

Sounds like the OP has a truck that is a factory lemon. Maybe a good one to let go. I don’t think the factory has any recourse when you show the oil samples that state the engine is already failing.

I worked 40 years in the industry, that oil report is fatal not imagination.