2023 AT4 Engine Crankshaft gone 4500 miles

[PhxPhk]

Was driving along and all of the sudden the truck started to buck, I thought it might be the transmission but it seemed to stop then notice Power going away started to hear the lifters or something make a lot of noises. I was nearly able to get off the road in a safe place. Then it would not start had to call roadside assistance to tow.
Another problem was we couldn’t get the truck in neutral because there is no release CRAZY.
They tell me i now have to wait two to maybe three months before the can replace the engine.

 

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[Teegunn]

Which engine do you have?

2 to 3 months is a long time... hope they can give you a loaner or you have another vehicle you can use in the meantime.

 

[PhxPhk]

Which engine do you have?

2 to 3 months is a long time... hope they can give you a loaner or you have another vehicle you can use in the meantime.

6.2 liter and yes loner but nowhere near my truck. Only had since mid November.
Was on first road trip.

 

[Teegunn]

6.2 liter and yes loner but nowhere near my truck. Only had since mid November.
Was on first road trip.

Damn, that sucks. I have a 23 AT4X with the 6.2. Just over two months of ownership now.

At least you have a loaner, but still, 3 months is too long to expect someone to wait.

 

[Andystoy AT4]

Any codes or warning lights when the engine quit? The transmission is electronically shifted so putting the shifter in neutral should have allowed the transmission to shift to neutral unless there is a problem with the transmission as well. Was the truck towed on a dolly?

 

[clojczyc]

Hi all,

Just signed up to this forum to add that I also just had my 6.2l engine fail on my Yukon. Dealership said that the crankshaft bearing spun. Vehicle had 5000km on it and just bought it back in December 2022. No noise occurred or check engine lights came on. Engine just quit and I coasted to the side of the highway.

 

[PhxPhk]

Any codes or warning lights when the engine quit? The transmission is electronically shifted so putting the shifter in neutral should have allowed the transmission to shift to neutral unless there is a problem with the transmission as well. Was the truck towed on a dolly?

No warning lights at first then check engine light came on and the truck stopped. Could not shift into neutral because no power.
They had to block the rear ties to get on tow truck.

 

[PhxPhk]

Hi all,

Just signed up to this forum to add that I also just had my 6.2l engine fail on my Yukon. Dealership said that the crankshaft bearing spun. Vehicle had 5000km on it and just bought it back in December 2022. No noise occurred or check engine lights came on. Engine just quit and I coasted to the side of the highway.

Exactly what happened to me

 

[clojczyc]

Exactly what happened to me

Is your dealership replacing your entire engine? I was told they are just going to replace the damaged parts.

 

[PhxPhk]

Is your dealership replacing your entire engine? I was told they are just going to replace the damaged parts.

 

[PhxPhk]

They told me they’re going to replace the whole engine.

 

[Andystoy AT4]

Unfortunately an interesting scenario, ask the dealership if the engine has been disassembled or sent back to GM complete? They used to do that with major engine failures like yours so that they could take it apart and determine what caused the failure. I suspect that the first failure was oil pressure related (loss) causing a bearing(s) to fail and seize that is why I asked about the codes or warning lights.
The fact that you had no power seems to point to something like an auto start failure which shouldn't be related to the first failure.
Just speculation on my part but if you can more info as the repairs are made it would be interesting to the followers and owners on AT4.

 

[PhxPhk]

Unfortunately an interesting scenario, ask the dealership if the engine has been disassembled or sent back to GM complete? They used to do that with major engine failures like yours so that they could take it apart and determine what caused the failure. I suspect that the first failure was oil pressure related (loss) causing a bearing(s) to fail and seize that is why I asked about the codes or warning lights.
The fact that you had no power seems to point to something like an auto start failure which shouldn't be related to the first failure.
Just speculation on my part but if you can more info as the repairs are made it would be interesting to the followers and owners on AT4.

The dealer said they have two other ones ahead of mine and that there is a batch of bad motors that they are seeing with the bad bearings.
Will keep posting updates.

 

[clojczyc]

Interesting. I’ll have to poke my dealer to see what all they are fixing. From what I gathered this was the first time they heard of this happening.

In regards to the failure, I thought it was an electronics issue and was surprised it was engine internal related when the failure happened as there was absolutely no indication that something had failed (didn’t hear any noise over the music from the radio). I had the vehicle in cruise at 115km/hr (70mph) and realized I was dropping speed then realized the engine wasn’t running and ended up coasting to the side of the highway.

 

[PhxPhk]

Interesting. I’ll have to poke my dealer to see what all they are fixing. From what I gathered this was the first time they heard of this happening.

In regards to the failure, I thought it was an electronics issue and was surprised it was engine internal related when the failure happened as there was absolutely no indication that something had failed (didn’t hear any noise over the music from the radio). I had the vehicle in cruise at 115km/hr (70mph) and realized I was dropping speed then realized the engine wasn’t running and ended up coasting to the side of the highway.

Yep almost the same was going 75 up and down hillside area then power was gone was barely able to pull off road safely.