Is this the tick?

[Geotrash]

Can you confirm if you hear this only after a cold start or at every idle even when engine is warm?

Also possible those are injectors...

No sir. That's a failed lifter. I'd bet a bottle of Willet Rye on it.

 

[SSGUNNER]

No sir. That's a failed lifter. I'd bet a bottle of Willet Rye on it.

How sure are you? Double up or nothing.

Being there are more than one vid in this thread which one are you referring to?? OP???

This is a failed lifter

 

[Geotrash]

How sure are you? Double up or nothing.

Being there are more than one vid in this thread which one are you referring to?? OP???

This is a failed lifter

I’ll go even one step further: it’s a failed DFM lifter… which is easy because that’s all that generation of engine has, but still . This video:

 

[SSGUNNER]

I’ll go even one step further: it’s a failed DFM lifter… which is easy because that’s all that generation of engine has, but still . This video:

Well after hearing this sound again with better airpods to me it does sound more of a knock which is strange because it’s not continuous. At first to me it did sound like injectors similar to these:

Check at 5:20

It’ll be interesting to know what this other member reports back.

 

[808RST]

yes, at cold start and after the engine is warm at idle......I'll update this thread with what the diagnosis is

Well after hearing this sound again with better airpods to me it does sound more of a knock which is strange because it’s not continuous. At first to me it did sound like injectors similar to these:

Check at 5:20

It’ll be interesting to know what this other member reports back.

Well, I got the Tahoe back this evening from the dealership with no luck. They said that it sounds like a lifter (both service advisor and mechanic) however without it producing an error code, they don't know which one failed and which bank to open up. Mechanic said he even test drove it and listened to the engine and couldn't reproduce the sound. I had to show him the same video I posted here. Their advice, just keep driving the thing and when it fails, they'll fix it. That's very comforting especially if I take it on a trip and get stuck in the middle of nowhere. They also mentioned something about the GM Bulletin saying if it's under 8K miles they only replace the broken lifters and if over 8K they replace all lifters. Don't quote me on that, but take it for what it's worth.

Thanks @SSGUNNER and @Geotrash for your insight.......sorry to hijack the thread.